Random access method, terminal, and network device

ABSTRACT

This application provides a random access method, a terminal, and a network device. The random access method includes: determining, by a terminal, whether a resource used for random access conflicts with a resource used for receiving a downlink signal; and if the resource used for the random access conflicts with the resource used for the downlink signal, preferentially using the conflicting random access resource for receiving the downlink signal but not for the random access. This avoids a conflict between receiving of the downlink signal and sending of an uplink random access preamble.

CROSS-REFERENCE TO RELATED APPLICATIONS

This Application is a continuation of International Application No.PCT/CN2018/116254, filed on Nov. 19, 2018, which claims priority ofChinese Patent Application No. 201711149117.6, filed on Nov. 17, 2017,The disclosures of the aforementioned applications are herebyincorporated by reference in their entireties.

TECHNICAL FIELD

This application relates to the wireless communications field, and inparticular, to a random access method, a terminal, and a network device.

BACKGROUND

In a new radio (NR) technology, a base station sends a downlink signalby using a plurality of beams. The downlink signal may be a downlinksynchronization signal block (SS/PBCH block), a system informationblock, remaining minimum system information, a system information block1 NR SIB1, a system information block 0 NR SIB0, a semi-staticallyconfigured downlink subframe and/or slot and/or OFDM symbol, a reserveddownlink signal, a downlink demodulation reference signal (DMRS), or adownlink channel state information-reference signal (CSI-RS).Specifically, the base station covers a cell by using the plurality ofbeams. During communication between the base station and a terminal, anappropriate beam direction is required for performing communication. Thebase station requires the appropriate beam direction for receiving arandom access preamble sent by the terminal, sending a random accessresponse to the terminal, and the like. The downlink signal is sent in atime division manner. To be specific, different downlink signals aresent in different time periods, and random access preambles sent by theterminal are also received in different time periods. In addition, inthe NR technology, a maximum quantity of downlink signals in onedownlink signal set may vary depending on different frequency bands. Forexample, below 3 gigahertz (GHz), the maximum quantity of downlinksignals in one downlink signal set is 4; at 3-6 GHz, the maximumquantity of downlink signals in one downlink signal set is 8; above 6GHz, the maximum quantity of downlink signals in one downlink signal setis 64. All downlink signals in a downlink signal set are mapped todifferent slots and orthogonal frequency division multiplexing (OFDM)symbols within a 5-millisecond (ms) window.

Specifically, a downlink signal set is sent periodically, and a quantityof actually sent downlink signals in a downlink signal set may not be amaximum quantity. For example, below 6 GHz, eight bits are used toindicate whether eight downlink signals are actually sent; above 6 GHz,whether downlink signals are actually sent is indicated in an 8+8manner: 64 downlink signals are divided into eight groups, each groupincludes eight downlink signals, eight bits are used to indicate whetherthe downlink signals in each group are sent, and another eight bits areused to indicate whether eight downlink signal sets are sent.

However, a period for sending a downlink signal set in the NR technologyis relatively short. A minimum period may be 5 ms. In other words,downlink signals may be sent in nearly all slots in one system frame.Correspondingly, a random access preamble sent by the terminal isconfigured in an uplink time, and therefore a time in which the basestation sends a downlink signal may conflict with a time in which theterminal sends an uplink random access preamble. The foregoingdiscussion is a discussion regarding ongoing design efforts for the NRand is not an admission of being prior art.

SUMMARY

This application provides a random access method, a terminal, and anetwork device, to resolve a problem that a time in which a base stationsends a downlink signal may conflict with a time in which a terminalsends an uplink random access preamble.

According to a first aspect, this application provides a random accessmethod, including:

determining, by a terminal, an actually available random accessresources based on time location information for a random accessresource and time location information for a downlink signal actuallysent by a network device, where a time location for the actuallyavailable random access resource does not overlap with the time locationfor the actually sent downlink signal;

determining, by the terminal based on the actually available randomaccess resource and an association relationship between a downlinksignal and a random access resource, a target random access resourcecorresponding to the actually sent downlink signal; and

sending, by the terminal, a random access preamble to the network deviceby using the target random access resource.

According to a second aspect, this application provides a random accessmethod, including:

when determining that a time location for an actually transmitteddownlink signal overlaps with a time location for a random accessresource, determining, by a terminal, to puncture the random accessresource whose time location overlaps with the time location for theactually sent downlink signal; or determining to puncture the randomaccess resource whose time location overlaps with the time location forthe actually sent downlink signal, and all random access resources thatprecede the random access resource whose time location overlaps with thetime location for the actually sent downlink signal and that are in aslot in which the random access resource whose time location overlapswith the time location for the actually sent downlink signal is located;or determining to puncture all random access resources in a slot inwhich the random access resource whose time location overlaps with thetime location for the actually sent downlink signal is located.

In a possible embodiment, the determining, by a terminal, an actuallyavailable random access resource based on time location information fora random access resource and time location information for a downlinksignal actually sent by a network device includes:

determining, by the terminal based on the time location information forthe random access resource and the time location information for thedownlink signal actually sent by the network device, the random accessresource whose time location overlaps with the time location for theactually sent downlink signal; and

using, by the terminal as the actually available random access resource,a random access resource whose time location does not overlap with thetime location for the actually sent downlink signal.

In a possible embodiment, after the determining, by the terminal, therandom access resource whose time location overlaps with the timelocation for the actually sent downlink signal, the method furtherincludes:

puncturing, by the terminal, the random access resource whose timelocation overlaps with the time location for the actually sent downlinksignal; or

puncturing, by the terminal, the random access resource whose timelocation overlaps with the time location for the actually sent downlinksignal, and all the random access resources that precede the randomaccess resource whose time location overlaps with the time location forthe actually sent downlink signal and that are in the slot in which therandom access resource whose time location overlaps with the timelocation for the actually sent downlink signal is located; or

puncturing, by the terminal, all the random access resources in the slotin which the random access resource whose time location overlaps withthe time location for the actually sent downlink signal is located.

In a possible embodiment, the downlink signal is one or more of thefollowing: a downlink synchronization signal block, a system informationblock, remaining minimum system information, a new radio systeminformation block 1 NR SIB1, a new radio system information block 0 NRSIB0, a semi-statically configured downlink subframe, a semi-staticallyconfigured slot, a semi-statically configured OFDM symbol, or a reserveddownlink signal.

In a possible embodiment, the method further includes:

receiving, by the terminal, configuration information sent by thenetwork device, where the configuration information indicates one ormore of the following: the slot in which the random access resource islocated is based on a subcarrier spacing of a random access message 1,the slot in which the random access resource is located is based on asubcarrier spacing of a random access message 3, the slot in which therandom access resource is located is based on a subcarrier spacing ofuplink initial access bandwidth, the slot in which the random accessresource is located is based on a subcarrier spacing of a downlinksignal, or a length of the slot in which the random access resource islocated.

In a possible embodiment, the time location for the downlink signal isdetermined based on one or more of the following: a slot occupied by thedownlink signal, an OFDM symbol occupied by the downlink signal, or adownlink/uplink guard period, where the slot is based on a subcarrierspacing of the downlink signal.

In a possible embodiment, the method further includes:

determining, by the terminal based on the time location information forthe random access resource and time location information for asemi-persistent scheduling signal, a semi-persistent scheduling signalwhose time location overlaps with the time location for the randomaccess resource; and

puncturing, by the terminal, the semi-persistent scheduling signal whosetime location overlaps with the time location for the random accessresource.

In a possible embodiment, the method further includes:

determining, by the terminal based on the time location information forthe random access resource and time location information for asemi-persistent scheduling signal, a random access resource whose timelocation overlaps with the time location for the semi-persistentscheduling signal; and

puncturing, by the terminal, the random access resource whose timelocation overlaps with the time location for the semi-persistentscheduling signal; or

puncturing, by the terminal, the random access resource whose timelocation overlaps with the time location for the semi-persistentscheduling signal, and all random access resources that precede therandom access resource whose time location overlaps with the timelocation for the semi-persistent scheduling signal and that are in aslot in which the random access resource whose time location overlapswith the time location for the semi-persistent scheduling signal islocated; or

puncturing, by the terminal, all random access resources in a slot inwhich the random access resource whose time location overlaps with thetime location for the semi-persistent scheduling signal is located.

In a possible embodiment, the method further includes:

adding, by the terminal, a new random access resource in a K^(th) uplinkslot before or after an uplink slot in which a punctured random accessresource is located, and using the new random access resource as anactually available random access resource, where K is a preset orpreconfigured constant; or

adding, by the terminal, a new random access resource in afrequency-domain location of an uplink slot in which the random accessresource whose location does not overlap with the location of theactually sent downlink signal is located, and using the new randomaccess resource as an actually available random access resource; or

adding, by the terminal, a new random access resource in anotherorthogonal frequency division multiplexing OFDM symbol of an uplink slotin which the random access resource whose location does not overlap withthe location of the actually sent downlink signal is located, and usingthe new random access resource as an actually available random accessresource.

In a possible embodiment, the method further includes:

determining, by the terminal, a quantity of punctured random accessresources based on a random access preamble format and a quantity ofoverlapping OFDM symbols that are between the actually sent downlinksignal and the random access resource and that are in the slot in whichthe random access resource is located.

In a possible embodiment, before the determining, by the terminal basedon the actually available random access resources and an associationrelationship between a downlink signal and a random access resource, atarget random access resource corresponding to the actually sentdownlink signal, the method further includes:

updating, by the terminal, the association relationship between adownlink signal and a random access resource based on the actually sentdownlink signal(s) and the actually available random access resources,to obtain a new association relationship between a downlink signal and arandom access resource.

According to a third aspect, this application provides a random accessmethod, including:

determining, by a network device, an actually available random accessresource based on time location information for a random access resourceand time location information for a downlink signal actually sent by thenetwork device, where a time location for the actually available randomaccess resource does not overlap with the time location for the actuallysent downlink signal;

determining, by the network device based on the actually availablerandom access resources and an association relationship between adownlink signal and a random access resource, a target random accessresource corresponding to the actually sent downlink signal; and

receiving, by the network device based on the target random accessresource corresponding to the actually sent downlink signal, a randomaccess preamble sent by a terminal.

In a possible embodiment, the determining, by a network device, anactually available random access resource based on time locationinformation for a random access resource and time location informationfor a downlink signal actually sent by the network device includes:

determining, by the network device based on the time locationinformation for the random access resource and the time locationinformation for the downlink signal actually sent by the network device,a random access resource whose time location overlaps with the timelocation for the actually sent downlink signal; and

using, by the network device as the actually available random accessresource, a random access resource whose time location does not overlapwith the time location for the actually sent downlink signal.

In a possible embodiment, the downlink signal is one or more of thefollowing: a downlink synchronization signal block, a system informationblock, remaining minimum system information, a new radio systeminformation block 1 (NR SIB1), a new radio system information block 0(NR SIB0), a semi-statically configured downlink subframe, asemi-statically configured slot, a semi-statically configured OFDMsymbol, or a reserved downlink signal.

In a possible embodiment, the method further includes:

sending, by the network device, configuration information to theterminal, where the configuration information indicates one or more ofthe following: a slot in which the random access resource is located isbased on a subcarrier spacing of a random access message 1, a slot inwhich the random access resource is located is based on a subcarrierspacing of a random access message 3, a slot in which the random accessresource is located is based on a subcarrier spacing of uplink initialaccess bandwidth, a slot in which the random access resource is locatedis based on a subcarrier spacing of a downlink signal, or a length of aslot in which the random access resource is located.

In a possible embodiment, the time location for the downlink signal isdetermined based on one or more of the following: a slot occupied by thedownlink signal, an OFDM symbol occupied by the downlink signal, or adownlink/uplink guard period, where the slot is based on a subcarrierspacing of the downlink signal.

In a possible embodiment, the method further includes:

determining, by the network device based on the time locationinformation for the random access resource and time location informationfor a semi-persistent scheduling signal, a semi-persistent schedulingsignal whose time location overlaps with the time location for therandom access resource.

In a possible embodiment, before the determining, by the network devicebased on the actually available random access resources and anassociation relationship between a downlink signal and a random accessresource, a target random access resource corresponding to the actuallysent downlink signal, the method further includes:

updating, by the network device, the association relationship between adownlink signal and a random access resource based on the actually sentdownlink signal(s) and the actually available random access resources,to obtain a new association relationship between a downlink signal and arandom access resource.

According to a fourth aspect, this application provides a random accessmethod, including:

when determining that a time location for an actually transmitteddownlink signal overlaps with a time location for a random accessresource, determining, by a network device, to puncture the randomaccess resource whose time location overlaps with the time location forthe actually sent downlink signal; or determining to puncture the randomaccess resource whose time location overlaps with the time location forthe actually sent downlink signal, and all random access resources thatprecede the random access resource whose time location overlaps with thetime location for the actually sent downlink signal and that are in aslot in which the random access resource whose time location overlapswith the time location for the actually sent downlink signal is located;or determining to puncture all random access resources in a slot inwhich the random access resource whose time location overlaps with thetime location for the actually sent downlink signal is located.

According to a fifth aspect, this application provides a terminal,including:

a determining module, configured to: determine an actually availablerandom access resource based on time location information for a randomaccess resource and time location information for a downlink signalactually sent by a network device, where a time location for theactually available random access resource does not overlap with the timelocation for the actually sent downlink signal; and determine, based onthe actually available random access resources and an associationrelationship between a downlink signal and a random access resource, atarget random access resource corresponding to the actually sentdownlink signal; and a sending module, configured to send a randomaccess preamble to the network device by using the target random accessresource.

According to a sixth aspect, this application provides a terminal,including:

a determining module, configured to: when determining that a timelocation for an actually transmitted downlink signal overlaps with atime location for a random access resource, determine to puncture therandom access resource whose time location overlaps with the timelocation for the actually sent downlink signal; or determine to puncturethe random access resource whose time location overlaps with the timelocation for the actually sent downlink signal, and all random accessresources that precede the random access resource whose time locationoverlaps with the time location for the actually sent downlink signaland that are in a slot in which the random access resource whose timelocation overlaps with the time location for the actually sent downlinksignal is located; or determine to puncture all random access resourcesin a slot in which the random access resource whose time locationoverlaps with the time location for the actually sent downlink signal islocated.

In a possible embodiment, the determining module is specificallyconfigured to: determine, based on the time location information for therandom access resource and the time location information for thedownlink signal actually sent by the network device, the random accessresource whose time location overlaps with the time location for theactually sent downlink signal; and determine to use, as the actuallyavailable random access resource, a random access resource whose timelocation does not overlap with the time location for the actually sentdownlink signal.

In a possible embodiment, the determining module is further configuredto: determine to puncture the random access resource whose time locationoverlaps with the time location for the actually sent downlink signal;or determine to puncture the random access resource whose time locationoverlaps with the time location for the actually sent downlink signal,and all the random access resources that precede the random accessresource whose time location overlaps with the time location for theactually sent downlink signal and that are in the slot in which therandom access resource whose time location overlaps with the timelocation for the actually sent downlink signal is located; or determineto puncture all the random access resources in the slot in which therandom access resource whose time location overlaps with the timelocation for the actually sent downlink signal is located.

In a possible embodiment, the downlink signal is one or more of thefollowing: a downlink synchronization signal block, a system informationblock, remaining minimum system information, a new radio systeminformation block 1 (NR SIB1), a new radio system information block 0(NR SIB0), a semi-statically configured downlink subframe, asemi-statically configured slot, a semi-statically configured OFDMsymbol, or a reserved downlink signal.

In a possible embodiment, the method further includes:

a receiving module, configured to receive configuration information sentby the network device, where the configuration information indicates oneor more of the following: the slot in which the random access resourceis located is based on a subcarrier spacing of a random access message1, the slot in which the random access resource is located is based on asubcarrier spacing of a random access message 3, the slot in which therandom access resource is located is based on a subcarrier spacing ofuplink initial access bandwidth, the slot in which the random accessresource is located is based on a subcarrier spacing of a downlinksignal, or a length of the slot in which the random access resource islocated.

In a possible embodiment, the time location for the downlink signal isdetermined based on one or more of the following: a slot occupied by thedownlink signal, an OFDM symbol occupied by the downlink signal, or adownlink/uplink guard period, where the slot is based on a subcarrierspacing of the downlink signal.

In a possible embodiment, the determining module is further configuredto: determine, based on the time location information for the randomaccess resource and time location information for a semi-persistentscheduling signal, a semi-persistent scheduling signal whose timelocation overlaps with the time location for the random access resource;and determine to puncture the semi-persistent scheduling signal whosetime location overlaps with the time location for the random accessresource.

In a possible embodiment, the determining module is further configuredto: determine, based on the time location information for the randomaccess resource and time location information for a semi-persistentscheduling signal, a random access resource whose time location overlapswith the time location for the semi-persistent scheduling signal; anddetermine to puncture the random access resource whose time locationoverlaps with the time location for the semi-persistent schedulingsignal; or determine to puncture the random access resource whose timelocation overlaps with the time location for the semi-persistentscheduling signal, and all random access resources that precede therandom access resource whose time location overlaps with the timelocation for the semi-persistent scheduling signal and that are in aslot in which the random access resource whose time location overlapswith the time location for the semi-persistent scheduling signal islocated; or determine to puncture all random access resources in a slotin which the random access resource whose time location overlaps withthe time location for the semi-persistent scheduling signal is located.

In a possible embodiment, the determining module is further configuredto: determine to add a new random access resource in a K^(th) uplinkslot before or after an uplink slot in which a punctured random accessresource is located, and to use the new random access resource as anactually available random access resource, where K is a preset orpreconfigured constant; or determine to add a new random access resourcein a frequency-domain location of an uplink slot in which the randomaccess resource whose location does not overlap with the location of theactually sent downlink signal is located, and to use the new randomaccess resource as an actually available random access resource; ordetermine to add a new random access resource in another orthogonalfrequency division multiplexing OFDM symbol of an uplink slot in whichthe random access resource whose location does not overlap with thelocation of the actually sent downlink signal is located, and to use thenew random access resource as an actually available random accessresource.

In a possible embodiment, the determining module is further configuredto determine a quantity of punctured random access resources based on arandom access preamble format and a quantity of overlapping OFDM symbolsthat are between the actually sent downlink signal and the random accessresource and that are in the slot in which the random access resource islocated.

In a possible embodiment, the determining module is further configuredto determine to update an association relationship between a downlinksignal and a random access resource based on the actually sent downlinksignal(s) and the actually available random access resources, to obtaina new association relationship between a downlink signal and a randomaccess resource.

According to a seventh aspect, this application provides a networkdevice, including:

a determining module, configured to: determine an actually availablerandom access resource based on time location information for a randomaccess resource and time location information for a downlink signalactually sent by the network device, where a time location for theactually available random access resource does not overlap with the timelocation for the actually sent downlink signal; and determine, based onthe actually available random access resources and an associationrelationship between a downlink signal and a random access resource, atarget random access resource corresponding to the actually sentdownlink signal; and a receiving module, configured to receive, based onthe target random access resource corresponding to the actually sentdownlink signal, a random access preamble sent by a terminal.

According to an eighth aspect, this application provides a networkdevice, including:

a determining module, configured to: when determining that a timelocation for an actually transmitted downlink signal overlaps with atime location for a random access resource, determine to puncture therandom access resource whose time location overlaps with the timelocation for the actually sent downlink signal; or determine to puncturethe random access resource whose time location overlaps with the timelocation for the actually sent downlink signal, and all random accessresources that precede the random access resource whose time locationoverlaps with the time location for the actually sent downlink signaland that are in a slot in which the random access resource whose timelocation overlaps with the time location for the actually sent downlinksignal is located; or determine to puncture all random access resourcesin a slot in which the random access resource whose time locationoverlaps with the time location for the actually sent downlink signal islocated.

According to a ninth aspect, this application provides an apparatus. Theapparatus includes a processor and a memory. The memory is configured tostore a program. The processor invokes the program stored in the memory,to perform the method provided in the first aspect or the second aspectin this application. The apparatus may be a terminal, or may be a chipon a terminal.

According to a tenth aspect, this application provides an apparatus. Theapparatus includes a processor and a memory. The memory is configured tostore a program. The processor invokes the program stored in the memory,to perform the method provided in the third aspect or the fourth aspectin this application. The apparatus may be a network device, or may be achip on a network device.

According to an eleventh aspect, this application provides a computerstorage medium. The computer storage medium is configured to store aprogram. The program is used to perform any one of the methods accordingto the first to the fourth aspects.

According to the random access method, the terminal, and the networkdevice that are provided in this application, the terminal determinesthe actually available random access resources based on the informationabout the location of the random access resource and the time locationinformation for the downlink signal actually sent by the network device;determines, based on the actually available random access resources andthe association relationship between a downlink signal and a randomaccess resource, the target random access resource corresponding to theactually sent downlink signal; and further sends the random accesspreamble to the network device by using the target random accessresource. This avoids a conflict between the actually sent downlinksignal and the random access preamble sent in uplink.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic architectural diagram of a communications systemaccording to this application;

FIG. 2 is a schematic flowchart of a random access method according toan embodiment of this application;

FIG. 3 is a schematic flowchart of a random access method according toanother embodiment of this application;

FIG. 4 is a schematic diagram of a resource structure according to thisapplication;

FIG. 5 is a schematic diagram of another resource structure according tothis application;

FIG. 6 is a schematic diagram of another resource structure according tothis application;

FIG. 7 is a schematic diagram of another resource structure according tothis application;

FIG. 8 is a schematic diagram of another resource structure according tothis application;

FIG. 9 is a schematic diagram of still another resource structureaccording to this application;

FIG. 10 is a schematic diagram of another resource structure accordingto this application;

FIG. 11 is a schematic diagram of still another resource structureaccording to this application;

FIG. 12 is a schematic diagram of another resource structure accordingto this application;

FIG. 13 is a schematic diagram of still another resource structureaccording to this application;

FIG. 14 is a schematic diagram of another resource structure accordingto this application;

FIG. 15 is a schematic diagram of still another resource structureaccording to this application;

FIG. 16(a) to FIG. 16(g) are schematic diagrams of random accesspreamble formats according to this application;

FIG. 17(a) to FIG. 17(g) are schematic diagrams of random accesspreamble formats according to this application;

FIG. 18 is a schematic structural diagram of a terminal according to anembodiment of this application;

FIG. 19 is a schematic structural diagram of a terminal according toanother embodiment of this application;

FIG. 20 is a schematic structural diagram of a network device accordingto an embodiment of this application;

FIG. 21 is a schematic structural diagram of a network device accordingto another embodiment of this application;

FIG. 22 is a simplified schematic structural diagram of a terminaldevice; and

FIG. 23 is a simplified schematic structural diagram of a networkdevice.

DESCRIPTION OF EMBODIMENTS

The embodiments of this application may be applied to a wirelesscommunications system. It should be noted that the wirelesscommunications system mentioned in the embodiments of this applicationincludes but is not limited to: a Narrowband Internet of Things (NB-IoT)system, a Global System for Mobile Communications (GSM), an EnhancedData rates for GSM Evolution (EDGE) system, a Wideband Code DivisionMultiple Access (WCDMA) system, a Code Division Multiple Access 2000(CDMA 2000) system, a Time Division-Synchronous Code Division MultipleAccess (TD-SCDMA) system, a Long Term Evolution (LTE) system, and threeapplication scenarios of a next-generation 5G mobile communicationssystem: Enhanced Mobile Broadband (eMBB), URLLC, and massive machinetype communication (mMTC).

In the embodiments of this application, a terminal includes but is notlimited to a mobile station (MS), a mobile terminal, a mobile phone, ahandset, a portal device, and the like. The terminal may communicatewith one or more core networks through a radio access network (RAN). Forexample, the terminal may be a mobile phone (or referred to as a“cellular” phone) or a computer with a wireless communication function.The terminal may also be a portable, pocket-sized, handheld, computerbuilt-in, or in-vehicle mobile apparatus or device.

FIG. 1 is a schematic architectural diagram of a communications systemaccording to this application.

As shown in FIG. 1, the communications system 01 includes a networkdevice 101 and a terminal 102. When the wireless communications network01 includes a core network, the network device 101 may be furtherconnected to the core network. The network device 101 may furthercommunicate with an Internet Protocol (IP) network 200, such as theInternet, a private IP network, or another data network. A networkdevice provides a service for a terminal in a coverage area of thenetwork device. For example, as shown in FIG. 1, the network device 101provides wireless access for one or more terminals in a coverage area ofthe network device 101. In addition, network devices may furthercommunicate with each other.

The network device 101 may be a device configured to communicate with aterminal. For example, the network device 101 may be a base transceiverstation (BTS) in a GSM system or a CDMA system; or may be a NodeB (NB)in a WCDMA system; or may be an evolved NodeB (eNB or eNodeB) in an LTEsystem, or a network-side device in a future 5G network. Alternatively,the network device may be a relay node, an access point, an in-vehicledevice, or the like. In a device-to-device (D2D) communications system,the network device may alternatively be a terminal that functions as abase station. The terminal may include various handheld devices,in-vehicle devices, wearable devices, and computing devices that have awireless communication function, or other processing devices connectedto wireless modems; user equipments (UE) and mobile stations (MS) thatare in various forms; and the like.

In this application, a random access (RACH) resource may includeinformation such as a random access time and a random access frequency.The random access time may be an orthogonal frequency divisionmultiplexing (OFDM) symbol, a mini-slot, a slot, a subframe, or a timesegment whose duration is H basic time units; and indicates a timerequired for sending a predefined random access preamble. The randomaccess frequency indicates bandwidth required for sending a predefinedrandom access preamble. H is greater than 0. In an implementation, onerandom access resource is identified in two dimensions: a random accesstime and a random access frequency. In other words, one random accesstime and one random access frequency define one random access resource.In another implementation, one random access time and one random accessfrequency may define a plurality of random access resources.

One random access resource may also be referred to as one random accessoccasion (RACH occasion/RACH transmission occasion/RACH opportunity/RACHchance, RO), or one random access preamble or one set of a plurality ofrandom access preambles that is on one random access time-frequencyresource. In this application, the terms “a” or “an” is used to includeone or more. Reference to an element in a singular is intended to mean“one or more” and not to mean “one and only one” unless specificallystated.

FIG. 2 is a schematic flowchart of a random access method according toan embodiment of this application. As shown in FIG. 2, the methodincludes the following steps.

S201: A terminal determines an actually available random access resourcebased on time location information for a random access resource and timelocation information for a downlink signal actually sent by a networkdevice.

A location of the actually available random access resource does notoverlap with the location of the actually sent downlink signal.

Optionally, the network device sends first configuration information tothe terminal, where the first configuration information carries one ormore of the following information: a frame format configuration index, asemi-static uplink/downlink configuration (semi-static UL/DLconfiguration), semi-persistent downlink or uplink scheduling(semi-persistent scheduling), a random access configuration index, arandom access preamble subcarrier spacing, indication information of theactually sent downlink signal, downlink signal set periodicityinformation, random access configuration periodicity (RACH configurationperiodicity) information, uplink channel information, or slot formatinformation (SFI); and/or

the network device sends second configuration information to theterminal, where the second configuration information includes at leastone of the following: a slot in which the random access resource islocated is based on a subcarrier spacing of a random access message 1(MSG1), a slot in which the random access resource is located is basedon a subcarrier spacing of a random access message 3 (MSG3), a slot inwhich the random access resource is located is based on a subcarrierspacing of uplink initial access bandwidth, a slot in which the randomaccess resource is located is based on a subcarrier spacing of adownlink signal, a slot in which the random access resource is locatedis based on a subcarrier spacing of partial downlink initial accessbandwidth, or a length of a slot in which the random access resource islocated.

The downlink signal may be one or more of the following: asynchronization signal block (SS block), a system information block,remaining minimum system information (RMSI), a new radio systeminformation block 1 (NR SIB1), a new radio system information block 0(NR SIB0), a reserved downlink signal, a semi-statically configureddownlink subframe, a semi-statically configured slot, or asemi-statically configured OFDM symbol.

The actually transmitted downlink signal may be corresponding to one ormore OFDM symbols. The downlink signal includes at least one of thefollowing: a primary synchronization signal (PSS), a secondarysynchronization signal (SSS), a physical broadcast signal (PBCH), ademodulation reference signal (DMRS). An SS block may also be referredto as an SS/PBCH block. A plurality of signals in the SS block or theSS/PBCH block may be sent by using a same antenna port.

Semi-static configuration means that an uplink/downlink communicationconfiguration appears periodically based on duration of a configurationperiod. In other words, a corresponding uplink/downlink subframe, slot,or OFDM symbol appears periodically. The period may be one or two slots,0.5 milliseconds, 1 millisecond, 2 milliseconds, 5 milliseconds, 10milliseconds, or another value corresponding to a 120-kHz subcarrierspacing. Semi-persistent scheduling means that time and frequencyresources used for uplink/downlink communication appear periodicallybased on duration of a scheduling period. In other words, a frequencyresource in a corresponding uplink/downlink subframe, slot, or OFDMsymbol appears periodically. The semi-persistent scheduling is alsoreferred to as semi-static scheduling (semi-static scheduling).

It should be understood that the reserved downlink signal is downlinkdata and/or null data carried in a reserved resource element and/orresource block in a reserved time.

A downlink signal set includes one or more downlink signals.

The uplink channel information may include one or more of the following:uplink center frequency information, an uplink channel number, uplinkchannel bandwidth, a quantity of uplink frequency bands, an uplinkfrequency band start location, an uplink frequency band subcarrieroffset value, an uplink frequency band resource block offset value, aquantity and/or bandwidth of partial uplink initial access bandwidth, asubcarrier spacing of partial uplink initial access bandwidth, or aquantity of random access resources. The uplink channel bandwidth may betotal uplink channel bandwidth, or may be uplink initial accessbandwidth. This is not limited in this application.

The terminal may obtain, based on the foregoing configurationinformation, the time location information for the random accessresource, the time location information for the actually sent downlinksignal, and the like.

Optionally, the semi-static uplink/downlink configuration is performedbased on a same subcarrier width. For example, the semi-staticuplink/downlink configuration is performed based on a subcarrier widthof a downlink signal, RMSI, uplink random access information 1, oruplink random access information 3.

Optionally, the semi-static uplink/downlink configuration is performedbased on a same subcarrier width. For example, the semi-staticuplink/downlink configuration is performed based on a largest orsmallest subcarrier in subcarriers of a downlink signal, RMSI, uplinkrandom access information 1, and uplink random access information 3.

Optionally, the semi-static uplink/downlink configuration is performedbased on different subcarrier widths. For example, downlinkconfiguration is performed based on a largest or smallest subcarrierwidth in subcarrier widths of a downlink signal and RMSI; and uplinkconfiguration is performed based on a largest or smallest subcarrierwidth in subcarrier widths of uplink random access information 1 anduplink random access information 3.

Optionally, the semi-static uplink/downlink configuration is performedbased on a same subcarrier width. In a low-frequency scenario (afrequency band is lower than a first preset frequency band),configuration is performed based on a fixed subcarrier width (forexample, 15 kHz). In a high-frequency scenario (a frequency band ishigher than a second preset frequency band), configuration is performedbased on another fixed subcarrier width (for example, 60 kHz).Alternatively, at a high and low frequency, configuration is performedbased on a same subcarrier width (15 kHz or 60 kHz).

Optionally, the terminal may determine quantity and time information ofuplink subframes, slots, and OFDM symbols in a system frame based on theframe format configuration index and/or the slot format information.Further, the terminal may determine, based on the random accessconfiguration index and the random access preamble subcarrier spacing,quantity and time information of uplink subframes, slots, and OFDMsymbols in which random access resources are located.

Further, the terminal determines the actually available random accessresources with reference to the indication information of the actuallysent downlink signal and the downlink signal set periodicityinformation.

S202: The terminal determines, based on the actually available randomaccess resources and an association relationship between a downlinksignal and a random access resource, a target random access resourcecorresponding to the actually sent downlink signal.

To be specific, the target random access resource corresponding to theactually sent downlink signal is determined from the actually availablerandom access resources. In other words, uplink information is not sentby using a random access resource whose location overlaps (which mayalso be understood as partially overlapping, conflicting, occupying, andthe like (overlap/conflict/occupy/overlay/intersect/cross) in thisapplication) with the location of the actually sent downlink signal.

S203: The terminal sends a random access preamble to the network deviceby using the target random access resource.

In this embodiment, the terminal determines the actually availablerandom access resources based on the information about the location ofthe random access resource and the time location information for thedownlink signal actually sent by the network device; determines, basedon the actually available random access resources and the associationrelationship between a downlink signal and a random access resource, thetarget random access resource corresponding to the actually sentdownlink signal; and further sends the random access preamble to thenetwork device by using the target random access resource. This avoids aconflict between the actually sent downlink signal and the random accesspreamble sent in uplink.

Correspondingly, a network-side device also determines an actuallyavailable random access resource and a target random access resource, toreceive a specific random access preamble.

FIG. 3 is a schematic flowchart of a random access method according toanother embodiment of this application. As shown in FIG. 3, the methodincludes the following steps.

S301: A network device determines an actually available random accessresource based on time location information for a random access resourceand time location information for an actually sent downlink signal,where a location of the actually available random access resource doesnot overlap with the location of the actually sent downlink signal.

Similarly, the network device may determine quantity and timeinformation of uplink subframes, slots, and OFDM symbols in a systemframe based on a frame format configuration index and/or slot formatinformation. Further, the network device may determine, based on arandom access configuration index and a random access preamblesubcarrier spacing, quantity and time information of uplink subframes,slots, and OFDM symbols in which random access resources are located.

Further, the network device determines the actually available randomaccess resources with reference to indication information of theactually sent downlink signal and downlink signal set periodicityinformation.

S302: The network device determines, based on the actually availablerandom access resources and an association relationship between adownlink signal and a random access resource, a target random accessresource corresponding to the actually sent downlink signal.

S303: The network device receives, based on the target random accessresource corresponding to the actually sent downlink signal, a randomaccess preamble sent by a terminal.

It should be noted that the network device and the terminal follow asame rule to determine related parameters, such as the actuallyavailable random access resources, the association relationship betweena downlink signal and a random access resource, and the target randomaccess resource. To be specific, the network device is aware of randomaccess resource on which the terminal sends random access preamble, andfurther receives the random access preamble on the random accessresource, to complete a random access process; and the network devicealso determines random access resource on which the terminal does notsend a random access preamble.

In this embodiment, the network device may determine the actuallyavailable random access resources based on the time location informationfor the random access resource and the time location information for theactually sent downlink signal, where the location of the actuallyavailable random access resources does not overlap with the location ofthe actually sent downlink signal; and determines, based on the actuallyavailable random access resources and the association relationshipbetween a downlink signal and a random access resource, the targetrandom access resource corresponding to the actually sent downlinksignal; and further receives, based on the target random access resourcecorresponding to the actually sent downlink signal, the random accesspreamble sent by the terminal. This avoids a conflict between theactually sent downlink signal and the random access preamble sent inuplink.

The time location for the downlink signal may be determined based on oneor more of the following: a slot occupied by the downlink signal, anOFDM symbol occupied by the downlink signal, or a downlink/uplink guardperiod, where the slot is based on a subcarrier spacing of the downlinksignal, and the downlink/uplink guard period is a period of time.

Based on the foregoing embodiments, that a terminal determines anactually available random access resource based on time locationinformation for a random access resource and time location informationfor a downlink signal actually sent by a network device may be:determining, based on the time location information for the randomaccess resource and the time location information for the downlinksignal actually sent by the network device, a random access resourcewhose time location overlaps with the time location for the actuallysent downlink signal; and further using, as the actually availablerandom access resource, a random access resource whose time locationdoes not overlap with the time location for the actually sent downlinksignal.

Specifically, the terminal determines that the random access resourcewhose time location overlaps with the time location for the actuallysent downlink signal is unavailable, to be specific, does not send therandom access preamble by using the random access resource whose timelocation overlaps with the time location for the actually sent downlinksignal. Correspondingly, the random access resource whose time locationdoes not overlap with the time location for the actually sent downlinksignal is determined as the actually available random access resource.

That the terminal determines that the random access resource whose timelocation overlaps with the time location for the actually sent downlinksignal is unavailable may be: puncturing (which may also be understoodas deletion, release, and the like (puncture/release/delete/remove) inthis application) the random access resource whose time locationoverlaps with the time location for the actually sent downlink signal.

According to a same principle, the terminal determines that the randomaccess resource whose time location overlaps with the time location forthe actually sent downlink signal is unavailable, to be specific, norandom access preamble needs to be received on the part whose timelocation overlaps with the time location for the actually sent downlinksignal.

In this application, a slot in which the random access resource islocated is based on a subcarrier spacing of at least one of thefollowing signals: a random access message 1 (MSG1), a random accessmessage 3 (MSG3), uplink initial access bandwidth, downlink initialaccess bandwidth, a downlink synchronization signal block, systeminformation (for example, a new radio system information block 1 (NRSIB1), or a new radio system information block 0 (NR SIB0)), remainingminimum system information (remaining minimum system information, RMSI),or other downlink signals (for example, a semi-statically configureddownlink subframe and/or slot and/or OFDM symbol); or a length of a slotin which the random access resource is located is indicated by thenetwork device.

The new radio system information block 1 (NR SIB1), the new radio systeminformation block 0 (NR SIB0), and the downlink signal aresemi-statically configured downlink subframes and/or slots and/or OFDMsymbols. One or more of the downlink signals are reserved downlinksignals.

In this application, the time location for the downlink signal is theslot and/or the OFDM symbol occupied by the downlink signal, where theslot and/or the OFDM symbol are/is based on the subcarrier spacing ofthe downlink signal.

The time location for the downlink signal may further include thedownlink/uplink guard period (guard period, for example, used for uplinkand downlink switchover). The downlink/uplink guard period is a periodof time.

In this application, subcarrier spacings of a downlink synchronizationsignal block, a system information block, remaining minimum systeminformation, a new radio system information block 1 (NR SIB1), a newradio system information block 0 (NR SIB0), a semi-statically configureddownlink subframe and/or slot and/or OFDM symbol, a reserved downlinksignal, a semi-persistently scheduled downlink subframe and/or slotand/or OFDM symbol, a downlink demodulation reference signal, and adownlink channel state information-reference signal are different fromsubcarrier spacings of an uplink PRACH, a semi-statically configureduplink subframe and/or slot and/or OFDM symbol, a reserved uplinksignal, and a semi-persistently scheduled uplink subframe and/or slotand/or OFDM symbol. Therefore, corresponding time scales, such as slotsor OFDM symbol lengths, are also different, and a difference betweensubcarriers of different signals needs to be considered duringadjustment of a random access resource.

Specifically, an adjustment manner applied when a downlinksynchronization signal block overlaps with a random access resource isused as an example for description. It should be noted that, in theembodiments herein, the downlink synchronization signal block is basedon a time scale corresponding to a subcarrier of the downlinksynchronization signal block, and the random access resource is based ona time scale corresponding to a subcarrier of a random access preamble.A similar resource puncturing and adjustment method is also applicableto adjustment performed when a time location for another downlink signal(with a different subcarrier spacing) overlaps with a time location fora random access resource.

In a specific implementation process, there may be the following cases(it should be noted that, in the accompanying drawings of thisapplication, “SS/PBCH” identifies a downlink signal (a downlinksynchronization signal block), and “PRACH” identifies a random accessresource).

(1) The terminal punctures the random access resource whose timelocation overlaps with the time location for the actually sent downlinksignal.

In this implementation, the terminal punctures the random accessresource whose time location overlaps with the time location for theactually sent downlink signal and that is in a slot in which the randomaccess resource whose time location overlaps with the time location forthe actually sent downlink signal is located, and retains another randomaccess resource, where the another random access resource may be furtherused as an actually available random access resource to continue to beused to send a random access preamble.

For example, the actually transmitted downlink signal occupies OFDMsymbols i to i+3 in time domain. In this case, it is determined thatrandom access resources in OFDM symbols iK to iK+4K−1 in time domain arenot to be used (for example, are punctured). K identifies a multiplebetween a subcarrier spacing of a random access resource and asubcarrier spacing of a downlink signal. For example, K may be any oneof the following: ¼, ½, 1, 2, or 4. i is an integer greater than orequal to 0.

FIG. 4 is a schematic diagram of a resource structure according to thisapplication. As shown in FIG. 4, when K=2, it is assumed that asubcarrier spacing of a downlink signal is 15 kilohertz (15 kHz), and asubcarrier spacing of a random access resource subcarrier spacing is 30kHz.

A maximum of one downlink signal may be transmitted within duration of aslot in which one random access resource is located. Specifically, theone downlink signal may be any downlink signal in a downlink signal set.As shown in FIG. 4, an actually sent downlink signal occupies OFDMsymbols 2 to 5 in a slot, and a random access resource may be placed inOFDM symbols 12 and 13 in a slot on a time scale of a random accessresource.

For another example, it is assumed that the actually sent downlinksignal occupies OFDM symbols 8 to 11 in a slot, and a random accessresource may be placed in OFDM symbols 10 to 13 in a slot on a timescale of a random access resource.

FIG. 5 is a schematic diagram of another resource structure according tothis application. As shown in FIG. 5, when K=½, it is assumed that asubcarrier spacing of a downlink signal is 30 kHz, and a subcarrierspacing of a random access resource is 15 kHz.

In this case, a maximum of four downlink signals may be transmittedwithin duration of a slot in which one random access resource islocated. The four downlink signals are denoted as downlink signals 0 to3, and may be any four downlink signals in a downlink signal set.

As shown in FIG. 5, an actually sent downlink signal occupies OFDMsymbols 2 to 5 and/or OFDM symbols 8 to 11 in a slot, and a randomaccess resource may be placed in OFDM symbols 10 to 13 in a slot on atime scale of a random access resource.

For another example, when the downlink signal 2 and the downlink signal3 are not transmitted, a random access resource may be placed in OFDMsymbols 6 to 13 in a slot on a time scale of a random access resource.

When the downlink signal 1, the downlink signal 2, and the downlinksignal 3 are not transmitted, a random access resource may be placed inOFDM symbols 3 to 13 in a slot on a time scale of a random accessresource.

Alternatively, when the actually sent downlink signal occupies OFDMsymbols 2 to 5 or OFDM symbols 6 to 9 in a slot, a random accessresource may be placed in OFDM symbols 10 to 13 in a slot on a timescale of a random access resource.

When the downlink signal 2 and the downlink signal 3 are nottransmitted, a random access resource may be placed in OFDM symbols 5 to13 in a slot on a time scale of a random access resource.

When the downlink signal 1, the downlink signal 2, and the downlinksignal 3 are not transmitted, a random access resource may be placed inOFDM symbols 3 to 13 in a slot on a time scale of a random accessresource.

It should be noted that, if a random access resource is configured basedon unslotted scheduling, the random access resource may be placed in anunslotted location occupied by an untransmitted downlink signal. Forexample, in unslotted scheduling based on seven OFDM symbols (on a timescale corresponding to a subcarrier spacing of a random accessresource), when the downlink signal 1 is not transmitted but thedownlink signal 2 is transmitted, OFDM symbols 3 to 6 of a time resourceoccupied by the downlink signal may be used to place a random accessresource. Alternatively, when the downlink signals 0 and 1 are nottransmitted but the downlink signal 2 is transmitted, OFDM symbols 0 to6 of a time resource occupied by the downlink signals may be used toplace a random access resource.

For another example, it is assumed that a subcarrier spacing of adownlink signal is 120 kHz, and a subcarrier spacing of a random accessresource is 60 kHz. In this case, a maximum of four downlink signals maybe transmitted within duration of a slot in which one random accessresource is located. For example, the four downlink signals are denotedas downlink signals 0 to 3, and may be any four downlink signals in adownlink signal set.

For example, transmission locations of the downlink signals arerespectively OFDM symbols 4 to 7, 8 to 11, 16 to 19, and 20 to 23 in twoadjacent slots (on a downlink signal time scale). When the downlinksignal 2 is transmitted but the downlink signal 3 is not transmitted, arandom access resource may be placed in OFDM symbols 10 to 13 in a sloton a time scale of a random access resource.

When the downlink signal 2 and the downlink signal 3 are nottransmitted, a random access resource may be placed in OFDM symbols 6 to13 in a slot on a time scale of a random access resource.

When the downlink signal 1, the downlink signal 2, and the downlinksignal 3 are not transmitted, a random access resource may be placed inOFDM symbols 4 to 13 in a slot k on a time scale of a random accessresource.

If a random access resource is configured based on unslotted scheduling(to be specific, OFDM symbols occupied by at least one configured randomaccess resource in time are less than one slot or 14 OFDM symbols, forexample, the random access resource occupies two, four, or seven OFDMsymbols, and a time scale of the OFDM symbols may be the same as ordifferent from a time scale of the random access resource), the randomaccess resource may be placed in an unslotted location occupied by anuntransmitted downlink signal. Specifically, in unslotted schedulingbased on seven OFDM symbols (on a time scale corresponding to asubcarrier spacing of a random access resource), when the downlinksignal 1 is not transmitted but the downlink signal 2 is transmitted,OFDM symbols 4 to 6 of a time resource occupied by the downlink signalmay be used to place a random access resource.

Alternatively, when the downlink signals 0 and 1 are not transmitted butthe downlink signal 2 is transmitted, OFDM symbols 0 to 6 of a timeresource occupied by the downlink signals may be used to place a randomaccess resource.

Alternatively, it is assumed that a subcarrier spacing of a downlinksignal is 240 kHz, and a subcarrier spacing of a random access resourceis 120 kHz. In this case, a maximum of four downlink signals may betransmitted within duration of a slot in which one random accessresource is located. For example, the four downlink signals are denotedas downlink signals 0 to 3, and may be any four downlink signals in adownlink signal set.

For example, transmission locations of the four downlink signals arerespectively OFDM symbols 8 to 11, 12 to 15, 16 to 19, and 20 to 23 intwo slots (on a downlink signal time scale). When the downlink signal 2is transmitted but the downlink signal 3 is not transmitted, a randomaccess resource may be placed in OFDM symbols 10 to 13 in a slot on atime scale of a random access resource.

When the downlink signal 2 and the downlink signal 3 are nottransmitted, a random access resource may be placed in OFDM symbols 8 to13 in a slot on a time scale of a random access resource.

When the downlink signal 1, the downlink signal 2, and the downlinksignal 3 are not transmitted, a random access resource may be placed inOFDM symbols 6 to 13 in a slot k on a time scale of a random accessresource.

If a random access resource is configured based on unslotted scheduling,the random access resource may be placed in an unslotted locationoccupied by an untransmitted downlink signal. For example, in unslottedscheduling based on seven OFDM symbols (on a time scale corresponding toa subcarrier spacing of a random access resource), when the downlinksignal 1 is not transmitted but the downlink signal 2 is transmitted, anOFDM symbol 6 of a time resource occupied by the downlink signal may beused to place a random access resource. Alternatively, when the downlinksignals 0 and 1 are not transmitted but the downlink signal 2 istransmitted, OFDM symbols 0 to 6 of a time resource occupied by thedownlink signals may be used to place a random access resource.

Alternatively, transmission locations of the four downlink signals arerespectively OFDM symbols 4 to 7, 8 to 11, 12 to 15, and 16 to 19 in twoslots (on a downlink signal time scale). When the downlink signal 2 istransmitted but the downlink signal 3 is not transmitted, a randomaccess resource may be placed in OFDM symbols 8 to 13 in a slot on atime scale of a random access resource.

When the downlink signal 2 and the downlink signal 3 are nottransmitted, a random access resource may be placed in OFDM symbols 6 to13 in a slot on a time scale of a random access resource.

When the downlink signal 1, the downlink signal 2, and the downlinksignal 3 are not transmitted, a random access resource may be placed inOFDM symbols 4 to 13 in a slot k on a time scale of a random accessresource.

If a random access resource is configured based on unslotted scheduling,the random access resource may be placed in an unslotted locationoccupied by an untransmitted downlink signal. For example, in unslottedscheduling based on seven OFDM symbols (on a time scale corresponding toa subcarrier spacing of a random access resource), when the downlinksignals 1 and 2 are not transmitted but the downlink signal 3 istransmitted, OFDM symbols 4 to 6 of a time resource occupied by thedownlink signals may be used to place a random access resource.Alternatively, when the downlink signals 0 to 2 are not transmitted butthe downlink signal 3 is transmitted, OFDM symbols 0 to 6 of a timeresource occupied by the downlink signals may be used to place a randomaccess resource.

FIG. 6 is a schematic diagram of another resource structure according tothis application. As shown in FIG. 6, K=1, in other words, a subcarrierspacing of a downlink signal is the same as a subcarrier spacing of arandom access resource, and both may be any one of 15 kHz, 30 kHz, or120 kHz.

A maximum of two downlink signals may be transmitted within duration ofa slot in which one random access resource is located. For example, thetwo downlink signals are denoted as downlink signals 0 and 1, and may beany two downlink signals in a downlink signal set.

As shown in FIG. 6, the first actually sent downlink signal 0 occupiesOFDM symbols 2 to 5 in a slot. In this case, if the downlink signal 1 isnot transmitted in the slot, a random access resource may be placed inOFDM symbols 6 to 13, occupied by the downlink signal, at a slot tail.For another example, the first downlink signal 0 occupies OFDM symbols 4to 7 in a slot. In this case, if the downlink signal 1 is nottransmitted in the slot, a random access resource may be placed in OFDMsymbols 8 to 13, occupied by the downlink signal, at a slot tail.

If a random access resource is configured based on unslotted scheduling(based on less than 14 OFDM symbols, for example, two, four, or sevenOFDM symbols), the random access resource may be placed in an unslottedlocation (an OFDM symbol location) occupied by an untransmitted downlinksignal. Particularly, unslotted scheduling based on seven OFDM symbolsis used as an example. When the downlink signal 0 is not transmitted butthe downlink signal 1 is transmitted, OFDM symbols 0 to 6 of a timeresource occupied by the downlink signal may be used to place a randomaccess resource.

In another possibility, K=¼, and it is assumed that a subcarrier spacingof a downlink signal is 240 kHz, and a subcarrier spacing of a randomaccess resource is 60 kHz.

In this case, a maximum of eight downlink signals may be transmittedwithin duration of a slot in which one random access resource islocated. For example, the eight downlink signals are denoted as downlinksignals 0 to 7, and may be any eight downlink signals in a downlinksignal set.

For example, transmission locations of the eight downlink signals arerespectively OFDM symbols 8 to 11, 12 to 15, 16 to 19, 20 to 23, 32 to35, 36 to 39, 40 to 43, and 44 to 47 in four slots (on a downlink signaltime scale). When the downlink signal 6 is transmitted but the downlinksignal 7 is not transmitted, a random access resource may be placed inOFDM symbols 11 to 13 in a slot on a time scale of a random accessresource.

When the downlink signal 5 is transmitted but the downlink signals 6 and7 are not transmitted, a random access resource may be placed in OFDMsymbols 10 to 13 in a slot on a time scale of a random access resource.

When the downlink signal 4 is transmitted but the downlink signals 5 to7 are not transmitted, a random access resource may be placed in OFDMsymbols 9 to 13 in a slot on a time scale of a random access resource.

When the downlink signal 3 is transmitted but the downlink signals 4 to7 are not transmitted, a random access resource may be placed in OFDMsymbols 7 to 13 in a slot on a time scale of a random access resource.

When the downlink signal 2 is transmitted but the downlink signals 6 and7 are not transmitted, a random access resource may be placed in OFDMsymbols 5 to 13 in a slot on a time scale of a random access resource.

When the downlink signal 1 is transmitted but the downlink signals 2 to7 are not transmitted, a random access resource may be placed in OFDMsymbols 4 to 13 in a slot on a time scale of a random access resource.

When the downlink signal 1 is transmitted but the downlink signals 1 to7 are not transmitted, a random access resource may be placed in OFDMsymbols 3 to 13 in a slot on a time scale of a random access resource.

If a random access resource is configured based on unslotted scheduling,the random access resource may be placed in an unslotted locationoccupied by an untransmitted downlink signal. For example, in unslottedscheduling based on seven OFDM symbols (on a time scale corresponding toa subcarrier spacing of a random access resource), when the downlinksignal 3 is not transmitted but any one of the downlink signals 4 to 7is transmitted, OFDM symbols 5 and 6 of a time resource occupied by thedownlink signal may be used to place a random access resource.Alternatively, when the downlink signals 2 and 3 are not transmitted butany one of the downlink signals 4 to 7 is transmitted, OFDM symbols 4 to6 of a time resource occupied by the downlink signals may be used toplace a random access resource. Alternatively, when the downlink signals1 to 3 are not transmitted but any one of the downlink signals 4 to 7 istransmitted, OFDM symbols 3 to 6 of a time resource occupied by thedownlink signals may be used to place a random access resource.Alternatively, when the downlink signals 0 and 3 are not transmitted butany one of the downlink signals 4 to 7 is transmitted, OFDM symbols 0 to6 of a time resource occupied by the downlink signals may be used toplace a random access resource.

(2) The terminal punctures the random access resource whose timelocation overlaps with the time location for the actually sent downlinksignal, and all random access resources that precede the random accessresource whose time location overlaps with the time location for theactually sent downlink signal and that are in a slot in which the randomaccess resource whose time location overlaps with the time location forthe actually sent downlink signal is located.

FIG. 7 is a schematic diagram of another resource structure according tothis application. As shown in FIG. 7, it is assumed that K=1.

It is determined that no random access preamble is to be sent on therandom access resource whose time location overlaps with the timelocation for the actually sent downlink signal. In addition, it isdetermined that no random access preamble is to be sent on a randomaccess resource that precedes this part of overlapping random accessresource and that is in the current slot either.

It should be noted that a random access preamble is sent in uplink, anda downlink signal is sent by the network device in downlink. The randomaccess resource that precedes this part of overlapping random accessresource and that is in the current slot is also punctured, to avoidfrequent uplink and downlink switchover.

(3) The terminal punctures all random access resources in a slot inwhich the random access resource whose time location overlaps with thetime location for the actually sent downlink signal is located.

FIG. 8 is a schematic diagram of another resource structure according tothis application. As shown in FIG. 8, it is assumed that K=2.

Similar to that in (2), to better avoid frequent uplink and downlinkswitchover, it is determined that no random access preamble is to besent in the slot in which the random access resource whose time locationoverlaps with the time location for the actually sent downlink signal islocated.

It should be noted that a manner of determining the actually availablerandom access resources by the network device may be used with referenceto that used on the terminal side. Details are not described again.

Based on the foregoing embodiments, because some original random accessresources are not used, in an implementation, an actually availablerandom access resource needs to be added.

Optionally, an available uplink slot and an uplink OFDM symbol locationin which no random access resource is placed may be first determined ina random access configuration period based on slot format configurationinformation (slot format information) and a downlink or uplink frameformat configuration.

Further, an added actually available random access resource may bedetermined based on a quantity of punctured random access resources.Specifically, a time location for the added actually available randomaccess resource, a quantity of added actually available random accessresources in frequency domain, and the like may be determined. The timelocation for the added random access resource may be at least one of asemi-statically configured uplink subframe, a semi-statically configureduplink slot, or a semi-statically configured uplink OFDM symbol. Inanother implementation, the time location for the added random accessresource may be a semi-statically configured undetermined uplink ordownlink subframe, slot, or OFDM symbol. The undetermined uplink ordownlink subframe, slot, or OFDM symbol is also referred to as anunknown subframe, slot, or OFDM symbol; and means that whether thesubframe, slot, or OFDM symbol is in an uplink or downlink direction isnot determined in random access; or means that the subframe, slot, orOFDM symbol is dynamically configured or scheduled through RRC, MAC CE,or DCI signaling in an uplink or downlink direction of the subframe,slot, or OFDM symbol.

Correspondingly, the network device also determines, in a same manner asthe terminal, a time location for an added actually available randomaccess resource, a quantity of added actually available random accessresources in frequency domain, and the like, to ensure that randomaccess preambles are to be received on some specific random accessresources.

In specific implementation, a random access resource may be added intime domain, frequency domain, or another uplink OFDM symbol location.

(1) In an optional solution, the terminal adds an actually availablerandom access resource in an uplink slot different from an uplink slotin which a punctured random access resource is located.

For example, the terminal adds a new random access resource in an uplinkslot adjacent to the uplink slot in which the punctured random accessresource is located, and uses the new random access resource as anactually available random access resource. For example, the randomaccess resource is added in a (K1)^(th) uplink subframe, slot, or OFDMsymbol before the uplink slot in which the punctured random accessresource is located. For another example, the random access resource isadded in a (K2) th uplink subframe, slot, or OFDM symbol before theuplink slot in which the punctured random access resource is located. K1and K2 are non-negative integers. Optionally, K1 and K2 are presetvalues, or values determined according to a preset rule. For example, K1and K2 each are fixedly one slot. Optionally, a quantity of added randomaccess resources is different from, for example, greater than, aquantity of punctured random access resources. Optionally, a quantity ofadded random access resources is different from, for example, less than,a quantity of punctured random access resources. Optionally, a quantityof random access resources to be added is determined based on a quantityof available uplink subframes, slots, or OFDM symbols.

FIG. 9 is a schematic diagram of still another resource structureaccording to this application. FIG. 10 is a schematic diagram of anotherresource structure according to this application.

As shown in FIG. 9 and FIG. 10, no downlink signal is transmitted in anuplink slot adjacent to an uplink slot in which a punctured randomaccess resource is located, and it is determined that some or allresources in the slot are used to transmit a random access preamble.

(2) In another optional solution, the terminal adds a new random accessresource in a frequency-domain location of an uplink slot in which arandom access resource whose location does not overlap with the locationof the actually sent downlink signal is located, and uses the new randomaccess resource as an actually available random access resource.

FIG. 11 is a schematic diagram of still another resource structureaccording to this application. FIG. 12 is a schematic diagram of anotherresource structure according to this application.

As shown in FIG. 11 and FIG. 12, a random access resource is added infrequency domain, and the newly added random access resource does notoverlap with an actually sent downlink signal in time either.

Optionally, a quantity of random access resources added in frequencydomain does not exceed channel bandwidth or initial uplink accessbandwidth configured by the network device.

(3) In still another optional solution, the terminal adds a new randomaccess resource in another OFDM symbol of an uplink slot in which arandom access resource whose location does not overlap with the locationof the actually sent downlink signal is located, and uses the new randomaccess resource as an actually available random access resource.Optionally, a quantity of random access resources to be added isdetermined based on a quantity of available uplink subframes, slots, orOFDM symbols.

FIG. 13 is a schematic diagram of still another resource structureaccording to this application. FIG. 14 is a schematic diagram of anotherresource structure according to this application.

As shown in FIG. 13 and FIG. 14, a new random access resource is addedin another OFDM symbol of a slot in which a punctured random resource islocated, and is used as an actually available random access resource.

Optionally, in time domain, the added random access resource may beevenly distributed in other uplink slots or OFDM symbol locations in arandom access configuration period. This is not limited herein.

(4) In an optional solution, the network device may indicate an uplinktime location for adding a random access resource, and the terminal addsa random access resource in the uplink time location indicated by thenetwork device.

There may be an alternative random access resource in the uplink timelocation for the random access resource that is indicated by the networkdevice. When a time location for an actually sent downlink signaloverlaps with a time location for a random access resource, or aquantity of random access resources whose time locations overlap with atime location for an actually sent downlink signal is greater than afirst preset threshold, or a quantity of actually sent downlink signalsis greater than a second preset threshold, the alternative random accessresource is activated.

It should be noted that different identifiers may be configured for theforegoing four solutions for adding a random access resource. Forexample, two bits are used for identification. The network device addsan identifier of “solution for adding a random access resource” to theconfiguration information, so that the terminal knows which solution isto be used to add a random access resource.

In addition, when the terminal sends a random access preamble on a newlyadded random access resource, a sending method is similar to a previoussending method. This is not limited herein.

Optionally, after it is determined that some random access resources areto be punctured, the random access configuration period may be furtheradjusted.

In a manner, random access resources in original N random accessconfiguration periods may be adjusted to be in M new random accessconfiguration periods. N and M may be any integers greater than 0. In anew random access configuration period, there is no random accessresource whose time location overlaps with a time location for adownlink signal.

Optionally, a total quantity of random access resources in the N randomaccess configuration periods before the adjustment is greater than atotal quantity of random access resources in the M new random accessconfiguration periods after the adjustment; or

a total quantity of random access resources in the N random accessconfiguration periods before the adjustment is equal to a total quantityof random access resources in the M new random access configurationperiods after the adjustment; or

a total quantity of random access resources in the N random accessconfiguration periods before the adjustment is less than a totalquantity of random access resources in the M new random accessconfiguration periods after the adjustment.

Optionally, a total quantity of random access resources in one randomaccess configuration period before the adjustment is greater than atotal quantity of random access resources in one new random accessconfiguration period after the adjustment; or

a total quantity of random access resources in one random accessconfiguration period before the adjustment is equal to a total quantityof random access resources in one new random access configuration periodafter the adjustment; or

a total quantity of random access resources in one random accessconfiguration period before the adjustment is less than a total quantityof random access resources in one new random access configuration periodafter the adjustment.

It should be noted that the adjusting the random access configurationperiod may include: adding and/or puncturing a random access resource.

FIG. 15 is a schematic diagram of still another resource structureaccording to this application. As shown in FIG. 15, an actuallytransmitted downlink signal, namely, a black part in a first row, isfirst determined.

Further, a random access configuration period is adjusted by addingand/or puncturing a random access resource.

Based on the foregoing embodiments, before S201, a random accessresource adjustment manner may be further determined based on one ormore of the actually sent downlink signal, a period for actually sendinga downlink signal, or a quantity of random access resources that are inone random access configuration period and whose time locations overlapwith the time location for the actually sent downlink signal.

For example, when the quantity of random access resources that are inone random access configuration period and whose time locations overlapwith the time location for the actually sent downlink signal is greaterthan a first preset threshold, it is determined that a random accessresource is to be added. For a specific manner of adding a random accessresource, refer to the embodiments shown in FIG. 9 to FIG. 14. Detailsare not described herein again.

Alternatively, when the quantity of random access resources that are inone random access configuration period and whose time locations overlapwith the time location for the actually sent downlink signal is lessthan or equal to a first preset threshold, it is determined that therandom access configuration period is to be adjusted.

Alternatively, based on the foregoing embodiments, before S201, theterminal may further determine a random access resource adjustmentmanner based on one or more of a downlink/uplink frame formatconfiguration, slot format configuration information, or random accessconfiguration information.

It should be noted that the terminal performs adjustment, and thenetwork device also needs to perform corresponding adjustment, forexample, adjust the association relationship between a downlink signaland a random access resource, or adjust the random access configurationperiod. Details are not described herein again.

Further, before determining, based on the actually available randomaccess resources and the association relationship between a downlinksignal and a random access resource, the target random access resourcecorresponding to the actually sent downlink signal, the terminal mayfurther update the association relationship between a downlink signaland a random access resource based on the actually sent downlinksignal(s) and the actually available random access resources, to obtaina new association relationship between a downlink signal and a randomaccess resource.

To be specific, because it is determined that some original randomaccess resources are unavailable, a new actually available random accessresource may have been further added, and therefore the associationrelationship between a downlink signal and a random access resource alsoneeds to be adaptively updated and adjusted.

After the adjustment, the terminal determines, based on the actuallyavailable random access resources and an adjusted associationrelationship between a downlink signal and a random access resource, thetarget random access resource corresponding to the actually sentdownlink signal.

Specifically, a downlink signal and/or a downlink signal grouporiginally associated with a punctured random access resource may beassociated with a remaining random access resource in the random accessconfiguration period.

Alternatively, a quantity of random access resources associated witheach of actually transmitted downlink signals is updated. An updatedquantity of random access resources associated with each of actuallytransmitted downlink signals is less than the original quantity ofrandom access resources associated with each downlink signal.

Alternatively, a quantity of random access resources associated with apart of actually transmitted downlink signals is updated. After theupdate, an updated quantity of random access resources associated withthis part of actually transmitted downlink signals is less than theoriginal quantity of random access resources associated with this partof actually transmitted downlink signals.

Alternatively, an adjusted random access configuration period remainsunchanged, a random access resource is added in the adjusted randomaccess configuration period, and a time location and/or a frequencylocation of a random access resource associated with each downlinksignal or some downlink signals are/is adjusted. In other words, anadded actually available random access resource is associated with eachactually sent downlink signal or some actually sent downlink signals.

Alternatively, an adjusted random access configuration period becomeslonger, and a time location and/or a frequency location of a randomaccess resource associated with each downlink signal or some downlinksignals are/is adjusted based on a random access resource in theadjusted random access configuration period.

Alternatively, an adjusted random access configuration period becomesshorter, and a time location and/or a frequency location of a randomaccess resource associated with each downlink signal or some downlinksignals are/is adjusted based on a random access resource in theadjusted random access configuration period.

Alternatively, it is determined, based on the adjusted random accessconfiguration period, that a manner of associating a downlink signal anda random access resource is to be changed. Specifically, one-to-oneassociation between an actually sent downlink signal and a random accessresource may be changed to association between a plurality of actuallysent downlink signals and one random access resource. Alternatively,association between a plurality of actually sent downlink signals andone random access resource may be changed to association between aplurality of actually sent downlink signals and a plurality of randomaccess resources. Alternatively, the association manner may be changedto mapping all actually sent downlink signals to a same random accessresource. Alternatively, the association manner may be changed toone-to-one association between some actually sent downlink signals andrandom access resources, and association between one random accessresource and a plurality of actually sent downlink signals in the otherpart of actually sent downlink signals.

Based on the foregoing embodiments, the time location for the randomaccess resource may overlap with a time location for a semi-persistentscheduling signal.

Among the actually sent downlink signal, the random access resource, andthe semi-persistent scheduling signal, the actually sent downlink signalhas a highest priority. Once time locations of the actually sentdownlink signal, the random access resource, and the semi-persistentscheduling signal overlap, the downlink signal is preferentially sent,and other signals are temporarily not transmitted.

Priorities of the random access resource and the semi-persistentscheduling signal may be configured according to an actual requirement.

Optionally, the terminal determines, based on the time locationinformation for the random access resource and the time locationinformation for the semi-persistent scheduling signal, a random accessresource whose time location overlaps with the time location for thesemi-persistent scheduling signal.

In a manner, a priority of the random access resource is higher than apriority of the semi-persistent scheduling signal, and the terminalpunctures a semi-persistent scheduling signal whose time locationoverlaps with the time location for the random access resource.

In another manner:

the random access resource whose time location overlaps with the timelocation for the semi-persistent scheduling signal is punctured; or

the random access resource whose time location overlaps with the timelocation for the semi-persistent scheduling signal, and all randomaccess resources that precede the random access resource whose timelocation overlaps with the time location for the semi-persistentscheduling signal and that are in a slot in which the random accessresource whose time location overlaps with the time location for thesemi-persistent scheduling signal is located are punctured; or

all random access resources in a slot in which the random accessresource whose time location overlaps with the time location for thesemi-persistent scheduling signal is located are punctured.

It should be noted that the network device also determines, based on thetime location information for the random access resource and timelocation information for a semi-persistent scheduling signal, a randomaccess resource whose time location overlaps with the time location forthe semi-persistent scheduling signal.

Specifically, the network device determines that no random accesspreamble is to be transmitted on the random access resource whose timelocation overlaps with the time location for the semi-persistentscheduling signal; or determines that no random access preamble is to betransmitted on the random access resource whose time location overlapswith the time location for the semi-persistent scheduling signal, or anyrandom access resource that precedes the random access resource whosetime location overlaps with the time location for the semi-persistentscheduling signal and that is in a slot in which the random accessresource whose time location overlaps with the time location for thesemi-persistent scheduling signal is located; or determines that norandom access preamble is to be transmitted on any random accessresource in a slot in which the random access resource whose timelocation overlaps with the time location for the semi-persistentscheduling signal is located.

Further, it should be noted that a random access preamble format may beone or more of formats in Table 1 in an existing standard: A0, A1, A2,A3, B0, B1, B2, B3, B4, C0, or C2; or may be one or more of formats inTable 2: 0, 1, 2, or 3. In practice, the formats A0 to C2 and theformats 0 to 3 may have other names. This is not limited herein.

Specifically, Table 1 lists a preamble format used when a sequencelength L is 127 or 139.

TABLE 1 Preamble Quantity of format OFDM symbols L Δf^(RA) N_(u) N_(CP)^(RA) N_(GT) ^(RA) A0 1 [127 or 139] 15 · 2^(μ) kHz   2048κ · 2^(−μ)144κ · 2^(−μ) 0 A1 2 [127 or 139] 15 · 2^(μ) kHz 2 · 2048κ · 2^(−μ) 288κ· 2^(−μ) 0 A2 4 [127 or 139] 15 · 2^(μ) kHz 4 · 2048κ · 2^(−μ) 576κ ·2^(−μ) 0 A3 6 [127 or 139] 15 · 2^(μ) kHz 6 · 2048κ · 2^(−μ) 864κ ·2^(−μ) 0 B1 2 [127 or 139] 15 · 2^(μ) kHz 2 · 2048κ · 2^(−μ) 216κ ·2^(−μ)  72κ · 2^(μ) B2 4 [127 or 139] 15 · 2^(μ) kHz 4 · 2048κ · 2^(−μ)360κ · 2^(−μ)  72κ · 2^(μ) B3 6 [127 or 139] 15 · 2^(μ) kHz 6 · 2048κ ·2^(−μ) 504κ · 2^(−μ) 360κ · 2^(μ) B4 12 [127 or 139] 15 · 2^(μ) kHz 12 ·2048κ · 2^(−μ)  936κ · 2^(−μ) 792κ · 2^(μ) C0 1 [127 or 139] 15 · 2^(μ)kHz   2048κ · 2^(−μ) 1240κ · 2^(−μ)  1096κ · 2^(μ)  C2 4 [127 or 139] 15· 2^(μ) kHz 4 · 2048κ · 2^(−μ) 2048κ · 2^(−μ)  2916κ · 2^(μ) 

Table 2 lists a preamble format used when a sequence length L is 839.

TABLE 2 Preamble format L Δf^(RA) N_(u) N_(CP) ^(RA) N_(GT) ^(RA) 0 8391.25 kHz 2457κ 3168κ 2976κ · 2^(u) 1 839 1.25 kHz   2.24576κ 21024κ 21904κ · 2^(u)  2 839 1.25 kHz   4.24576κ 4688κ 4528κ · 2^(u) 3 839   5kHz 2457κ 3168κ 2796κ · 2^(u)

κ=64. Δf^(RA) indicates a random access preamble subcarrier spacing.N_(u) indicates a length of a random access preamble sequence. N_(CP)^(RA) indicates a cyclic prefix (cyclic prefix, CP) length of a randomaccess preamble. N_(GT) ^(RA) indicates a guard period.

Based on the foregoing embodiments, the terminal may determine aquantity of punctured random access resources based on the random accesspreamble format and a quantity of overlapping OFDM symbols that arebetween the actually sent downlink signal and the random access resourceand that are in the slot in which the random access resource is located.

When there are two consecutive overlapping OFDM symbols between theactually sent downlink signal and the random access resource in the slotin which the random access resource is located, refer to Table 3.

TABLE 3 Format Quantity A0 1 A0 2 A1 1 B1 1 C1 1

It can be learned that, when there are two consecutive overlapping OFDMsymbols between the actually sent downlink signal and the random accessresource in the slot in which the random access resource is located, ifthe random access preamble format is A0, it is determined that thequantity of punctured random access resources is one or two OFDMsymbols; if the random access preamble format is A1, it is determinedthat the quantity of punctured random access resources is one OFDMsymbol; if the random access preamble format is B1, it is determinedthat the quantity of punctured random access resources is one OFDMsymbol; or if the random access preamble format is C1, it is determinedthat the quantity of punctured random access resources is one OFDMsymbol.

When there are three consecutive overlapping OFDM symbols between theactually sent downlink signal and the random access resource in the slotin which the random access resource is located, refer to Table 4.

TABLE 4 Format Quantity A0 1 A0 2 A0 3 A1 1 B1 1 C1 1

It can be learned that, when there are three consecutive overlappingOFDM symbols between the actually sent downlink signal and the randomaccess resource in the slot in which the random access resource islocated, if the random access preamble format is A0, it is determinedthat the quantity of punctured random access resources is one, two, orthree OFDM symbols; and so on. Details are not described again.

When there are four consecutive overlapping OFDM symbols between theactually sent downlink signal and the random access resource in the slotin which the random access resource is located, refer to Table 5.

TABLE 5 Format Quantity A0 1 A0 2 A0 3 A0 4 A1 3 A1 2 A2 1 B1 1 B1 2 B21 C1 1 C1 2

It can be learned that, when there are four consecutive overlapping OFDMsymbols between the actually sent downlink signal and the random accessresource in the slot in which the random access resource is located, ifthe random access preamble format is A0, it is determined that thequantity of punctured random access resources is one, two, three, orfour OFDM symbols; and so on. Details are not described again.

When there are five consecutive overlapping OFDM symbols between theactually sent downlink signal and the random access resource in the slotin which the random access resource is located, refer to Table 6.

TABLE 6 Format Quantity A0 1 A0 2 A0 3 A0 4 A0 5 A1 1 A1 2 A2 1 B1 1 B12 B2 1 C1 1 C1 2 C1 3

It can be learned that, when there are five consecutive overlapping OFDMsymbols between the actually sent downlink signal and the random accessresource in the slot in which the random access resource is located, ifthe random access preamble format is A0, it is determined that thequantity of punctured random access resources is one, two, three, four,or five OFDM symbols; and so on. Details are not described again.

When there are six consecutive overlapping OFDM symbols between theactually sent downlink signal and the random access resource in the slotin which the random access resource is located, refer to Table 7.

TABLE 7 Format Quantity A0 1 A0 2 A0 3 A0 4 A0 5 A0 6 A1 1 A1 2 A1 3 A21 A3 1 B1 1 B1 2 B1 3 B2 1 B3 1 C1 1 C1 2 C1 3

It can be learned that, when there are six consecutive overlapping OFDMsymbols between the actually sent downlink signal and the random accessresource in the slot in which the random access resource is located, ifthe random access preamble format is A0, it is determined that thequantity of punctured random access resources is one, two, three, four,five, or six OFDM symbols; and so on. Details are not described again.

When there are seven consecutive overlapping OFDM symbols between theactually sent downlink signal and the random access resource in the slotin which the random access resource is located, refer to Table 8.

TABLE 8 Format Quantity A0 1 A0 2 A0 3 A0 4 A0 5 A0 6 A0 7 A1 1 A1 2 A13 A2 1 A3 1 B1 1 B1 2 B1 3 B2 1 B3 1 C1 1 C1 2 C1 3 C1 4 C2 1

It can be learned that, when there are seven consecutive overlappingOFDM symbols between the actually sent downlink signal and the randomaccess resource in the slot in which the random access resource islocated, if the random access preamble format is A0, it is determinedthat the quantity of punctured random access resources is one, two,three, four, five, six, or seven OFDM symbols; and so on. Details arenot described again.

When there are eight consecutive overlapping OFDM symbols between theactually sent downlink signal and the random access resource in the slotin which the random access resource is located, refer to Table 9.

TABLE 9 Format Quantity A0 1 A0 2 A0 3 A0 4 A0 5 A0 6 A0 7 A0 8 A1 1 A12 A1 3 A1 4 A2 1 A2 2 A3 1 B1 1 B1 2 B1 3 B1 4 B2 1 B2 2 B3 1 C1 1 C1 2C1 3 C1 4 C1 5 C2 1

It can be learned that, when there are eight consecutive overlappingOFDM symbols between the actually sent downlink signal and the randomaccess resource in the slot in which the random access resource islocated, if the random access preamble format is A0, it is determinedthat the quantity of punctured random access resources is one, two,three, four, five, six, seven, or eight OFDM symbols; and so on. Detailsare not described again.

When there are nine consecutive overlapping OFDM symbols between theactually sent downlink signal and the random access resource in the slotin which the random access resource is located, refer to Table 10.

TABLE 10 Format Quantity A0 1 A0 2 A0 3 A0 4 A0 5 A0 6 A0 7 A0 8 A0 9 A11 A1 2 A1 3 A1 4 A2 1 A2 2 A3 1 B1 1 B1 2 B1 3 B1 4 B2 1 B2 2 B3 1 C1 1C1 2 C1 3 C1 4 C1 5 C2 1

It can be learned that, when there are nine consecutive overlapping OFDMsymbols between the actually sent downlink signal and the random accessresource in the slot in which the random access resource is located, ifthe random access preamble format is A0, it is determined that thequantity of punctured random access resources is one, two, three, four,five, six, seven, eight, or nine OFDM symbols; and so on. Details arenot described again.

When there are 10 consecutive overlapping OFDM symbols between theactually sent downlink signal and the random access resource in the slotin which the random access resource is located, refer to Table 11.

TABLE 11 Format Quantity A0 1 A0 2 A0 3 A0 4 A0 5 A0 6 A0 7 A0 8 A0 9 A010 A1 1 A1 2 A1 3 A1 4 A1 5 A2 1 A2 2 A3 1 B1 1 B1 2 B1 3 B1 4 B1 5 B2 1B2 2 B3 1 C1 1 C1 2 C1 3 C1 4 C1 5 C1 6 C2 1

It can be learned that, when there are 10 consecutive overlapping OFDMsymbols between the actually sent downlink signal and the random accessresource in the slot in which the random access resource is located, ifthe random access preamble format is A0, it is determined that thequantity of punctured random access resources is 1, 2, 3, 4, 5, 6, 7, 8,9, or 10 OFDM symbols; and so on. Details are not described again.

When there are 11 consecutive overlapping OFDM symbols between theactually sent downlink signal and the random access resource in the slotin which the random access resource is located, refer to Table 12.

TABLE 12 Format Quantity A0 1 A0 2 A0 3 A0 4 A0 5 A0 6 A0 7 A0 8 A0 9 A010 A0 11 A1 1 A1 2 A1 3 A1 4 A1 5 A2 1 A2 2 A3 1 B1 1 B1 2 B1 3 B1 4 B15 B2 1 B2 2 B3 1 C1 1 C1 2 C1 3 C1 4 C1 5 C1 6 C1 7 C2 1 C2 2

It can be learned that, when there are 11 consecutive overlapping OFDMsymbols between the actually sent downlink signal and the random accessresource in the slot in which the random access resource is located, ifthe random access preamble format is A0, it is determined that thequantity of punctured random access resources is 1, 2, 3, 4, 5, 6, 7, 8,9, 10, or 11 OFDM symbols; and so on. Details are not described again.

When there are 12 consecutive overlapping OFDM symbols between theactually sent downlink signal and the random access resource in the slotin which the random access resource is located, refer to Table 13.

TABLE 13 Format Quantity A0 1 A0 2 A0 3 A0 4 A0 5 A0 6 A0 7 A0 8 A0 9 A010 A0 11 A0 12 A1 1 A1 2 A1 3 A1 4 A1 5 A1 6 A2 1 A2 2 A2 3 A3 1 A3 2 B11 B1 1 B1 2 B1 3 B1 4 B1 5 B1 6 B2 1 B2 2 B2 3 B3 1 B3 2 C1 1 C1 2 C1 3C1 4 C1 5 C1 6 C1 7 C2 1 C2 2

It can be learned that, when there are 12 consecutive overlapping OFDMsymbols between the actually sent downlink signal and the random accessresource in the slot in which the random access resource is located, ifthe random access preamble format is A0, it is determined that thequantity of punctured random access resources is 1, 2, 3, 4, 5, 6, 7, 8,9, 10, 11, or 12 OFDM symbols; and so on. Details are not describedagain.

When there are 13 consecutive overlapping OFDM symbols between theactually sent downlink signal and the random access resource in the slotin which the random access resource is located, refer to Table 14.

TABLE 14 Format Quantity A0 1 A0 2 A0 3 A0 4 A0 5 A0 6 A0 7 A0 8 A0 9 A010 A0 11 A0 12 A0 13 A1 1 A1 2 A1 3 A1 4 A1 5 A1 6 A2 1 A2 2 A2 3 A3 1A3 2 B1 1 B1 1 B1 2 B1 3 B1 4 B1 5 B1 6 B2 1 B2 2 B2 3 B3 1 B3 2 C1 1 C12 C1 3 C1 4 C1 5 C1 6 C1 7 C1 8 C2 1 C2 2

It can be learned that, when there are 13 consecutive overlapping OFDMsymbols between the actually sent downlink signal and the random accessresource in the slot in which the random access resource is located, ifthe random access preamble format is A0, it is determined that thequantity of punctured random access resources is 1, 2, 3, 4, 5, 6, 7, 8,9, 10, 11, 12, or 13 OFDM symbols; and so on. Details are not describedagain.

It should be understood that, when a random access resource is added, aquantity of added random access preambles is related to duration,corresponding to a time scale of a random access preamble, of anavailable uplink subframe, slot, or OFDM symbol. For example, a quantityof added random access preambles in time is determined based on Table 1to Table 12, and the quantity of added random access preambles cannotexceed a maximum quantity allowed in a corresponding table.

FIG. 16(a) to FIG. 16(g) are schematic diagrams of random accesspreamble formats according to this application. Details are as follows.

In FIG. 16(a), N random access preamble formats A0 are continuouslydistributed in a subframe (subframe). At a corresponding subcarrierspacing, total duration of the N random access preamble formats A0 doesnot exceed one subframe. In another implementation, total duration ofthe N random access preamble formats A0 does not exceed K slots. K and Nare positive integers.

In FIG. 16(b), N random access preamble formats A1/B1 are continuouslydistributed in a subframe. At a corresponding subcarrier spacing, totalduration of the N random access preamble formats A1/B1 does not exceedone subframe. In another implementation, total duration of the N randomaccess preamble formats A1/B1 does not exceed K slots. K and N arepositive integers.

In FIG. 16(c), N random access preamble formats A2/B2 are continuouslydistributed in a subframe. At a corresponding subcarrier spacing, totalduration of the N random access preamble formats A2/B2 does not exceedone subframe. In another implementation, total duration of the N randomaccess preamble formats A2/B2 does not exceed K slots. K and N arepositive integers.

In FIG. 16(d), N random access preamble formats A3/B3 are continuouslydistributed in a subframe. At a corresponding subcarrier spacing, totalduration of the N random access preamble formats A3/B3 does not exceedone subframe. In another implementation, total duration of the N randomaccess preamble formats A3/B3 does not exceed K slots. K and N arepositive integers.

In FIG. 16(e), N random access preamble formats B4 are continuouslydistributed in a subframe. At a corresponding subcarrier spacing, totalduration of the N random access preamble formats B4 does not exceed onesubframe. In another implementation, total duration of the N randomaccess preamble formats B4 does not exceed K slots. K and N are positiveintegers.

In FIG. 16(f), N random access preamble formats C0 are continuouslydistributed in a subframe. At a corresponding subcarrier spacing, totalduration of the N random access preamble formats C0 does not exceed onesubframe. In another implementation, total duration of the N randomaccess preamble formats C0 does not exceed K slots. K and N are positiveintegers.

In FIG. 16(g), N random access preamble formats C2 are continuouslydistributed in a subframe. At a corresponding subcarrier spacing, totalduration of the N random access preamble formats C2 does not exceed onesubframe. In another implementation, total duration of the N randomaccess preamble formats C2 does not exceed K slots. K and N are positiveintegers.

FIG. 17(a) to FIG. 17(g) are schematic diagrams of random accesspreamble formats according to this application. Details are as follows.

In FIG. 17(a), N random access preamble formats A0 are continuouslydistributed in a slot. At a corresponding subcarrier spacing, totalduration of the N random access preamble formats A0 does not exceed oneslot. N is a positive integer.

In FIG. 17(b), N random access preamble formats A1/B1 are continuouslydistributed in a slot. At a corresponding subcarrier spacing, totalduration of the N random access preamble formats A1/B1 does not exceedone slot. N is a positive integer.

In FIG. 17(c), N random access preamble formats A2/B2 are continuouslydistributed in a slot. At a corresponding subcarrier spacing, totalduration of the N random access preamble formats A2/B2 does not exceedone slot. N is a positive integer.

In FIG. 17(d), N random access preamble formats A3/B3 are continuouslydistributed in a slot. At a corresponding subcarrier spacing, totalduration of the N random access preamble formats A3/B3 does not exceedone slot. N is a positive integer.

In FIG. 17(e), N random access preamble formats B4 are continuouslydistributed in a slot. At a corresponding subcarrier spacing, totalduration of the N random access preamble formats B4 does not exceed oneslot. N is a positive integer.

In FIG. 17(f), N random access preamble formats C0 are continuouslydistributed in a slot. At a corresponding subcarrier spacing, totalduration of the N random access preamble formats C0 does not exceed oneslot; or total duration of the N random access preamble formats C0 doesnot exceed K slots, where K is a positive integer. K and N are positiveintegers.

In FIG. 17(g), N random access preamble formats C2 are continuouslydistributed in a slot. At a corresponding subcarrier spacing, totalduration of the N random access preamble formats C2 does not exceed oneslot. K and N are positive integers.

It should be noted that two random access resource patterns in FIG.16(a) to FIG. 16(g) and in FIG. 17(a) to FIG. 17(g) may be indicated byconfiguration information of a base station, or may be preconfigured.For example, the manner shown in FIG. 16(a) to FIG. 16(g) is fixedlyused. For another example, the manner shown in FIG. 17(a) to FIG. 17(g)is fixedly used. When the manner is indicated by the network device, onebit may be used to indicate a Flag. When the Flag is 0, the manner shownin FIG. 16(a) to FIG. 16(g) is indicated; or when the Flag is 1, themanner shown in FIG. 17(a) to FIG. 17(g) is indicated. Alternatively,when the Flag is 1, the manner shown in FIG. 16(a) to FIG. 16(g) isindicated; or when the Flag is 0, the manner shown in FIG. 17(a) to FIG.17(g) is indicated.

FIG. 18 is a schematic structural diagram of a terminal according to anembodiment of this application. As shown in FIG. 18, the terminalincludes a determining module 181 and a sending module 182.

The determining module 181 is configured to: determine an actuallyavailable random access resource based on time location information fora random access resource and time location information for a downlinksignal actually sent by a network device, where a time location for theactually available random access resource does not overlap with the timelocation for the actually sent downlink signal; and determine, based onthe actually available random access resource and an associationrelationship between a downlink signal and a random access resource, atarget random access resource corresponding to the actually sentdownlink signal.

The sending module 182 is configured to send a random access preamble tothe network device by using the target random access resource.

Optionally, the determining module 181 is specifically configured to:determine, based on the time location information for the random accessresource and the time location information for the downlink signalactually sent by the network device, a random access resource whose timelocation overlaps with the time location for the actually sent downlinksignal; and determine to use, as the actually available random accessresource, a random access resource whose time location does not overlapwith the time location for the actually sent downlink signal.

Optionally, the determining module 181 is further configured to:determine to puncture the random access resource whose time locationoverlaps with the time location for the actually sent downlink signal;or determine to puncture the random access resource whose time locationoverlaps with the time location for the actually sent downlink signal,and all random access resources that precede the random access resourcewhose time location overlaps with the time location for the actuallysent downlink signal and that are in a slot in which the random accessresource whose time location overlaps with the time location for theactually sent downlink signal is located; or determine to puncture allrandom access resources in a slot in which the random access resourcewhose time location overlaps with the time location for the actuallysent downlink signal is located.

In an embodiment, the downlink signal is one or more of the following: adownlink synchronization signal block, a system information block,remaining minimum system information, a new radio system informationblock 1 NR SIB1, a new radio system information block 0 NR SIB0, asemi-statically configured downlink subframe, a semi-staticallyconfigured slot, a semi-statically configured OFDM symbol, or a reserveddownlink signal.

In another embodiment, the time location for the downlink signal isdetermined based on one or more of the following: a slot occupied by thedownlink signal, an OFDM symbol occupied by the downlink signal, or adownlink/uplink guard period, where the slot is based on a subcarrierspacing of the downlink signal, and the downlink/uplink guard period isa period of time.

This embodiment of the present invention and the foregoing methodembodiments are based on a same idea and bring a same technical effect.For a specific process, refer to the descriptions of the methodembodiments. Details are not described herein again.

FIG. 19 is a schematic structural diagram of a terminal according toanother embodiment of this application. As shown in FIG. 19, based onFIG. 18, the terminal further includes a receiving module 191,configured to receive configuration information sent by the networkdevice. The configuration information indicates one or more of thefollowing: the slot in which the random access resource is located isbased on a subcarrier spacing of a random access message 1, the slot inwhich the random access resource is located is based on a subcarrierspacing of a random access message 3, the slot in which the randomaccess resource is located is based on a subcarrier spacing of uplinkinitial access bandwidth, the slot in which the random access resourceis located is based on a subcarrier spacing of a downlink signal, or alength of the slot in which the random access resource is located.

Further, the determining module 181 is further configured to: determine,based on the time location information for the random access resourceand time location information for a semi-persistent scheduling signal, asemi-persistent scheduling signal whose time location overlaps with thetime location for the random access resource; and determine to puncturethe semi-persistent scheduling signal whose time location overlaps withthe time location for the random access resource.

Further, the determining module 181 is further configured to: determine,based on the time location information for the random access resourceand time location information for a semi-persistent scheduling signal, arandom access resource whose time location overlaps with the timelocation for the semi-persistent scheduling signal; and determine topuncture the random access resource whose time location overlaps withthe time location for the semi-persistent scheduling signal; ordetermine to puncture the random access resource whose time locationoverlaps with the time location for the semi-persistent schedulingsignal, and all random access resources that precede the random accessresource whose time location overlaps with the time location for thesemi-persistent scheduling signal and that are in a slot in which therandom access resource whose time location overlaps with the timelocation for the semi-persistent scheduling signal is located; ordetermine to puncture all random access resources in a slot in which therandom access resource whose time location overlaps with the timelocation for the semi-persistent scheduling signal is located.

In addition, the determining module 181 is further configured to:determine to add a new random access resource in a K^(th) uplink slotbefore or after an uplink slot in which a punctured random accessresource is located, and to use the new random access resource as anactually available random access resource, where K is a preset orpreconfigured constant; or determine to add a new random access resourcein a frequency-domain location of an uplink slot in which the randomaccess resource whose location does not overlap with the location of theactually sent downlink signal is located, and to use the new randomaccess resource as an actually available random access resource; ordetermine to add a new random access resource in another orthogonalfrequency division multiplexing OFDM symbol of an uplink slot in whichthe random access resource whose location does not overlap with thelocation of the actually sent downlink signal is located, and to use thenew random access resource as an actually available random accessresource.

Optionally, in an implementation, the determining module 181 is furtherconfigured to determine a quantity of punctured random access resourcesbased on a random access preamble format and a quantity of overlappingOFDM symbols that are between the actually sent downlink signal and therandom access resource and that are in the slot in which the randomaccess resource is located.

In another implementation, the determining module 181 is furtherconfigured to determine to update the association relationship between adownlink signal and a random access resource based on the actually sentdownlink signal and the actually available random access resources, toobtain a new association relationship between a downlink signal and arandom access resource.

This embodiment of the present invention and the foregoing methodembodiments are based on a same idea and bring a same technical effect.For a specific process, refer to the descriptions of the methodembodiments. Details are not described herein again.

FIG. 20 is a schematic structural diagram of a network device accordingto an embodiment of this application. As shown in FIG. 20, the networkdevice includes a determining module 211 and a receiving module 212.

The determining module 211 is configured to: determine an actuallyavailable random access resource based on time location information fora random access resource and time location information for a downlinksignal actually sent by the network device, where a time location forthe actually available random access resource does not overlap with thetime location for the actually sent downlink signal; and determine,based on the actually available random access resources and anassociation relationship between a downlink signal and a random accessresource, a target random access resource corresponding to the actuallysent downlink signal.

The receiving module 212 is configured to receive, based on the targetrandom access resource corresponding to the actually sent downlinksignal, a random access preamble sent by a terminal.

Optionally, the determining module 211 is specifically configured to:determine, based on the time location information for the random accessresource and the time location information for the downlink signalactually sent by the network device, a random access resource whose timelocation overlaps with the time location for the actually sent downlinksignal; and determine to use, as the actually available random accessresource, a random access resource whose time location does not overlapwith the time location for the actually sent downlink signal.

Optionally, the downlink signal is one or more of the following: adownlink synchronization signal block, a system information block,remaining minimum system information, a new radio system informationblock 1 NR SIB1, a new radio system information block 0 NR SIB0, asemi-statically configured downlink subframe, a semi-staticallyconfigured slot, a semi-statically configured OFDM symbol, or a reserveddownlink signal.

This embodiment of the present invention and the foregoing methodembodiments are based on a same idea and bring a same technical effect.For a specific process, refer to the descriptions of the methodembodiments. Details are not described herein again.

FIG. 21 is a schematic structural diagram of a network device accordingto another embodiment of this application. As shown in FIG. 21, based onFIG. 20, the network device further includes a sending module 213,configured to send configuration information to the terminal. Theconfiguration information indicates one or more of the following: a slotin which the random access resource is located is based on a subcarrierspacing of a random access message 1, a slot in which the random accessresource is located is based on a subcarrier spacing of a random accessmessage 3, a slot in which the random access resource is located isbased on a subcarrier spacing of uplink initial access bandwidth, a slotin which the random access resource is located is based on a subcarrierspacing of a downlink signal, or a length of a slot in which the randomaccess resource is located.

Optionally, the time location for the downlink signal is determinedbased on one or more of the following: a slot occupied by the downlinksignal, an OFDM symbol occupied by the downlink signal, or adownlink/uplink guard period, where the slot is based on a subcarrierspacing of the downlink signal, and the downlink/uplink guard period isa period of time.

Optionally, the determining module 211 is further configured todetermine to update the association relationship between a downlinksignal and a random access resource based on the actually sent downlinksignal(s) and the actually available random access resource, to obtain anew association relationship between a downlink signal and a randomaccess resource.

This embodiment of the present invention and the foregoing methodembodiments are based on a same idea and bring a same technical effect.For a specific process, refer to the descriptions of the methodembodiments. Details are not described herein again.

It should be noted that the module division of the apparatuses is merelylogical function division. In actual implementation, all or some of themodules may be integrated into one physical entity, or may be physicallyseparated. In addition, all of the modules may be implemented by aprocessing element invoking software; or all of the modules may beimplemented by hardware; or some of the modules may be implemented by aprocessing element invoking software, and some of the modules may beimplemented by hardware. For example, the determining module may be anindependent processing element; or may be integrated in a chip of theapparatuses. Alternatively, the determining module may be stored in amemory of the apparatuses in a form of program code, and invoked andexecuted by a processing element of the apparatuses. The apparatuses maybe configured to perform the methods provided in the foregoing methodembodiments. A specific implementation and a technical effect aresimilar to those of the method embodiments. Details are not describedherein again.

For example, the modules may be configured as one or more integratedcircuits for implementing the foregoing methods, for example, one ormore application-specific integrated circuits (ASIC), one or moremicroprocessors (DSP), or one or more field programmable gate arrays(FPGA). For another example, when one of the modules is implemented by aprocessing element by invoking program code, the processing element maybe a general-purpose processor, such as a central processing unit (CPU),or another processor that can invoke program code. For another example,the modules may be integrated, and implemented in a form of asystem-on-a-chip (SOC). Implementations of other modules are similar. Inaddition, some or all of the modules may be integrated, or may beindependently implemented. The processing element herein may be anintegrated circuit with a signal processing capability. In animplementation process, steps in the foregoing methods or the foregoingmodules may be implemented by using a hardware integrated logic circuitin the processing element, or by using instructions in a form ofsoftware.

For example, the modules may be configured as one or more integratedcircuits for implementing the foregoing methods, for example, one ormore application-specific integrated circuits (ASIC), one or moremicroprocessors (DSP), or one or more field programmable gate arrays(FPGA). For another example, when one of the modules is implemented by aprocessing element by invoking program code, the processing element maybe a general-purpose processor, such as a central processing unit (CPU),or another processor that can invoke program code. For another example,the modules may be integrated, and implemented in a form of asystem-on-a-chip (SOC).

FIG. 22 is a simplified schematic structural diagram of a terminaldevice. For ease of understanding and graphic illustration, in FIG. 22,an example in which the terminal device is a mobile phone is used.

As shown in FIG. 22, the terminal device includes a processor, a memory,a radio frequency circuit, an antenna, and an input/output apparatus.The processor is mainly configured to process a communication protocoland communication data, control the terminal device, execute a softwareprogram, process data of the software program, and the like. The memoryis mainly configured to store the software program and data. The radiofrequency circuit is mainly configured to perform conversion between abaseband signal and a radio frequency signal, and process a radiofrequency signal. The antenna is mainly configured to send or receive aradio frequency signal in a form of an electromagnetic wave. Theinput/output apparatus, such as a touchscreen, a display screen, or akeyboard, is mainly configured to receive data entered by a user, andoutput data to the user. It should be noted that some types of terminaldevices may not have an input/output apparatus.

When data needs to be sent, the processor performs baseband processingon the to-be-sent data, and outputs a baseband signal to the radiofrequency circuit. The radio frequency circuit performs radio frequencyprocessing on the baseband signal, and sends a radio frequency signal ina form of an electromagnetic wave through the antenna. When data is sentto the terminal device, the radio frequency circuit receives a radiofrequency signal through the antenna, converts the radio frequencysignal into a baseband signal, and outputs the baseband signal to theprocessor. The processor converts the baseband signal into data andprocesses the data. For ease of description, FIG. 22 shows only onememory and one processor. In an actual terminal device product, theremay be one or more processors and one or more memories. The memory mayalso be referred to as a storage medium, a storage device, or the like.The memory may be disposed independently from the processor, or may beintegrated with the processor. This is not limited in this embodiment ofthis application.

In this embodiment of this application, the antenna and the radiofrequency circuit that have a sending/receiving function may beconsidered as a receiving unit and a sending unit (or may becollectively referred to as a transceiver unit) of the terminal device,and the processor that has a processing function may be considered as aprocessing unit of the terminal device. As shown in FIG. 22, theterminal device includes a receiving unit 1201, a processing unit 1202,and a sending unit 1203. The receiving unit 1201 may also be referred toas a receiver, a receiver circuit, or the like. The sending unit 1203may also be referred to as a transmitter, a transmitter circuit, or thelike. The processing unit may also be referred to as a processor, aprocessing board, a processing module, a processing apparatus, or thelike.

For example, in an embodiment, the sending unit 1203 is configured toperform step S203 in the embodiment shown in FIG. 2.

FIG. 23 is a simplified schematic structural diagram of a networkdevice. The network device includes a radio frequency signalsending/receiving and conversion part and a part 1302. The radiofrequency signal sending/receiving and conversion part further includesa receiving unit part 1301 and a sending unit part 1303 (which may alsobe collectively referred to as a transceiver unit). The radio frequencysignal sending/receiving and conversion part is mainly configured tosend/receive a radio frequency signal and perform conversion between aradio frequency signal and a baseband signal. The part 1302 is mainlyconfigured to perform baseband processing, control the network device,and the like. The receiving unit 1301 may also be referred to as areceiver, a receiver circuit, or the like. The sending unit 1303 mayalso be referred to as a transmitter, a transmitter circuit, or thelike. The part 1302 is usually a control center of the network device,may be usually referred to as a processing unit, and is configured tocontrol the network device to perform steps performed by a secondcommunications apparatus in FIG. 5 or FIG. 9. For details, refer todescriptions in the foregoing related part.

The part 1302 may include one or more boards. Each board may include oneor more processors and one or more memories. The processor is configuredto read and execute a program in the memory, to implement a basebandprocessing function and control over the network device. If there are aplurality of boards, the boards may be interconnected to improve aprocessing capability. In an optional implementation, a plurality ofboards may share one or more processors, or a plurality of boards mayshare one or more memories, or a plurality of boards may share one ormore processors.

In another optional implementation, with development of a system-on-chip(SoC) technology, all or some of functions of the part 1302 and the part1301 may be implemented by using the SoC technology, for example,implemented by one base station function chip. The base station functionchip is integrated with devices such as a processor, a memory, and anantenna interface. A program of a function related to a base station isstored in the memory, and the processor executes the program toimplement the function related to the base station. Optionally, the basestation function chip can also read from an external memory of the chip,to implement a function related to the base station.

Optionally, when the random access methods in the foregoing embodimentsare fully or partially implemented by software, the terminal or thenetwork device may alternatively include only a processor. A memoryconfigured to store a program is located outside the apparatus. Theprocessor is connected to the memory by using a circuit or an electricalwire, to read and execute the program stored in the memory.

The processor may be a central processing unit (CPU), a networkprocessor (NP), or a combination of a CPU and an NP.

The processor may further include a hardware chip. The hardware chip maybe an application-specific integrated circuit (ASIC), a programmablelogic device (PLD), or a combination thereof. The PLD may be a complexprogrammable logic device (CPLD), a field programmable gate array(FPGA), a generic array logic (GAL), or any combination thereof.

The memory may include a volatile memory, such as a random access memory(RAM); or the memory may include a non-volatile memory, such as a flashmemory, a hard disk drive (HDD), or a solid-state drive (SSD); or thememory may include a combination of the foregoing types of memories.

An embodiment of this application further provides a computer storagemedium. The computer storage medium stores a computer program. Thecomputer program is used to perform the random access methods providedin the foregoing embodiments.

An embodiment of this application further provides a computer programproduct including an instruction. When the computer program product runson a computer, the computer is enabled to perform the random accessmethods provided in the foregoing embodiments.

A person skilled in the art should understand that the embodiments ofthis application may be provided as a method, a system, or a computerprogram product. Therefore, this application may use a form of hardwareonly embodiments, software only embodiments, or embodiments with acombination of software and hardware. In addition, this application mayuse a form of a computer program product that is implemented on one ormore computer-usable storage media (including but not limited to a diskmemory, a CD-ROM, an optical memory, and the like) that includecomputer-usable program code.

This application is described with reference to the flowcharts and/orblock diagrams of the method, the device (system), and the computerprogram product according to the embodiments of this application. Itshould be understood that computer program instructions may be used toimplement each process and/or each block in the flowcharts and/or theblock diagrams and a combination of a process and/or a block in theflowcharts and/or the block diagrams. These computer programinstructions may be provided for a general-purpose computer, a dedicatedcomputer, an embedded processor, or a processor of any otherprogrammable data processing device to generate a machine, so that theinstructions executed by a computer or a processor of any otherprogrammable data processing device generate an apparatus forimplementing a specific function in one or more processes in theflowcharts and/or in one or more blocks in the block diagrams.

These computer program instructions may be stored in a computer-readablememory that can instruct the computer or any other programmable dataprocessing device to work in a specific manner, so that the instructionsstored in the computer-readable memory generate an artifact thatincludes an instruction apparatus. The instruction apparatus implementsa specific function in one or more processes in the flowcharts and/or inone or more blocks in the block diagrams.

These computer program instructions may be loaded onto a computer oranother programmable data processing device, so that a series ofoperations and steps are performed on the computer or the anotherprogrammable device, thereby generating computer-implemented processing.Therefore, the instructions executed on the computer or the anotherprogrammable device provide steps for implementing a specific functionin one or more processes in the flowcharts and/or in one or more blocksin the block diagrams.

What is claimed is:
 1. A random access method, comprising: receivinginformation about random access resources from a network device;determining whether there is a random access resource that overlaps witha time resource for receiving a synchronization signal block; and ifthere is a random access resource overlaps with a time resource forreceiving a synchronization signal block, sending a random accesspreamble to the network device based on the random access resourcesexcluding the overlapping random access resource.
 2. The random accessmethod according to claim 1, wherein the determining whether there is arandom access resource that overlaps with a time resource for receivinga synchronization signal block, comprises: determining whether there isa symbol for random access that overlaps with a symbol for receiving thesynchronization signal block in a slot; if there is a symbol for randomaccess that overlaps with a symbol for receiving the synchronizationsignal block in the slot, the sending a random access preamble to thenetwork device based on the random access resources excluding theoverlapping random access resource, comprising: sending the randomaccess preamble to the network device without using the slot in whichthe overlapping symbols are located.
 3. The random access methodaccording to claim 1, wherein if there is a random access resource thatoverlaps with a time resource for receiving a synchronization signalblock, the method further comprising: determining the random accessresource that overlaps with the time resource for receiving thesynchronization signal block is unavailable for random access.
 4. Therandom access method according to claim 1, wherein the determiningwhether there is a random access resource that overlaps with a timeresource for receiving a synchronization signal block, comprises:determining whether there is a symbol for random access that overlapswith a symbol for receiving the synchronization signal block in a slot;if there is a symbol that overlaps with a symbol for receiving asynchronization signal block in the slot, the sending a random accesspreamble to the network device based on the random access resourcesexcluding the overlapping random access resource comprises: sending therandom access preamble without using the overlapping symbols in the slotand any symbol that precedes the overlapping symbols in the slot.
 5. Therandom access method according to claim 1, further comprising:determining whether there is a random access resource that overlaps witha time resource for receiving a semi-persistent scheduling signal, ifthere is a random access resource that overlaps with a time resource forreceiving a semi-persistent scheduling signal, not using the overlappingresource for receiving the semi-persistent scheduling signal.
 6. Therandom access method according to claim 1, further comprising:determining whether there is a symbol for random access that overlapswith a symbol for receiving a semi-persistent scheduling signal in aslot; if there is a symbol for random access that overlaps with a symbolfor receiving the semi-persistent scheduling signal block in the slot,not using the slot for receiving the semi-persistent scheduling signalin which the overlapping symbols are located.
 7. The random accessmethod according to claim 1, further comprising: determining the timeresource for receiving the synchronization signal block based on one ormore of the following: a slot occupied by the synchronization signalblock, an orthogonal frequency division multiplexing (OFDM) symboloccupied by the synchronization signal block, or a guard period.
 8. Therandom access method according to claim 1, wherein the information aboutrandom access resources from a network device comprises random accessconfiguration index and the random access preamble subcarrier spacing;the method further comprising: obtain the random access resources basedon the random access configuration index and the random access preamblesubcarrier spacing.
 9. An apparatus, comprising: one or more memoriesconfigured to store instructions; and one or more processors coupled tothe one or more memories and configured to execute the instructions,cause the apparatus to: receive information about random accessresources from a network device; determine whether there is a randomaccess resource that overlaps with a time resource for receiving asynchronization signal block; and if there is a random access resourceoverlaps with a time resource for receiving a synchronization signalblock, send a random access preamble to the network device based on therandom access resources excluding the overlapping random accessresource.
 10. The apparatus according to claim 9, the one or moreprocessors are further configured to execute the program instructions,cause the apparatus to: determine whether there is a symbol for randomaccess that overlaps with a symbol for receiving the synchronizationsignal block in a slot; if there is a symbol for random access thatoverlaps with a symbol for receiving the synchronization signal block inthe slot, send the random access preamble to the network device withoutusing the slot in which the overlapping symbols are located.
 11. Theapparatus according to claim 9, the one or more processors are furtherconfigured to execute the program instructions, cause the apparatus to:determine the random access resource that overlaps with the timeresource for receiving the synchronization signal block is unavailablefor random access.
 12. The apparatus according to claim 9, the one ormore processors are further configured to execute the programinstructions, cause the apparatus to: determine whether there is asymbol for random access that overlaps with a symbol for receiving thesynchronization signal block in a slot; if there is a symbol thatoverlaps with a symbol for receiving a synchronization signal block inthe slot, send the random access preamble without using the overlappingsymbols in the slot and any symbol that precedes the overlapping symbolsin the slot.
 13. The apparatus according to claim 9, the one or moreprocessors are further configured to execute the program instructions,cause the apparatus to: determine whether there is a random accessresource that overlaps with a time resource for receiving asemi-persistent scheduling signal, if there is a random access resourcethat overlaps with a time resource for receiving a semi-persistentscheduling signal, not using the overlapping resource for receiving thesemi-persistent scheduling signal.
 14. The apparatus according to claim9, the one or more processors are further configured to execute theprogram instructions, cause the apparatus to: determine whether there isa symbol for random access that overlaps with a symbol for receiving thesemi-persistent scheduling signal in a slot; if there is a symbol forrandom access that overlaps with a symbol for receiving thesemi-persistent scheduling signal block in the slot, not use the slotfor receiving the semi-persistent scheduling signal in which theoverlapping symbols are located.
 15. The apparatus according to claim 9,the one or more processors are further configured to execute the programinstructions, cause the apparatus to: determine the time resource forreceiving the synchronization signal block based on one or more of thefollowing: a slot for the synchronization signal block, an orthogonalfrequency division multiplexing (OFDM) symbol for the synchronizationsignal block, or a guard period.
 16. The apparatus according to claim 9,wherein the information about random access resources from a networkdevice comprises random access configuration index and the random accesspreamble subcarrier spacing; the one or more processors are furtherconfigured to execute the program instructions, cause the apparatus to:obtain the random access resources based on the random accessconfiguration index and the random access preamble subcarrier spacing.17. A random access method for a communications system, comprising:determining at least one actually available random access resource basedon time location information for random access resources and timelocation information for receiving a downlink signal, wherein a timelocation for the at least one actually available random access resourcedoes not overlap with a time location for receiving the downlink signal;and sending a random access preamble to a network device based on the atleast one actually available random access resource.
 18. The methodaccording to claim 17, further comprising: receiving a random accessconfiguration index, and obtaining the time location information for therandom access resources based on the random access configuration index.19. The method according to claim 17, further comprising: if it isdetermined that a time location for a random access resource overlapswith the time location for receiving the downlink signal, sending therandom access preamble without using the random access resource whosetime location overlaps with the time location for the downlink signal.20. The method according to claim 17, wherein if it is determined that atime location for a random access resource overlaps with the timelocation for receiving the downlink signal, the overlapping resource isprioritized for receiving the downlink signal.
 21. The method accordingto claim 17, further comprising: if it is determined that a timelocation for a random access resource overlaps with the time locationfor receiving the downlink signal, sending the random access preamblewithout using any random access resource that precedes the overlappingrandom access resource in an overlapping slot in which the overlappingrandom access resource is located.
 22. The method according to claim 17,wherein the time location is one or more of the following: an orthogonalfrequency division multiplexing (OFDM) symbol, a mini-slot, a slot, asubframe, or a time segment whose duration is H basic time units,wherein H is greater than
 0. 23. The method according to claim 17,wherein the downlink signal is one or more of the following: asynchronization signal block, a system information block, remainingminimum system information (RMSI), a new radio system information block1 (NR SIB1), a new radio system information block 0 (NR SIB0), areserved downlink signal, a semi-statically configured downlinksubframe, a semi-statically configured slot, or a semi-staticallyconfigured OFDM symbol.
 24. An apparatus, comprising: one or morememories configured to store instructions; and one or more processorscoupled to the one or more memories and configured to execute theinstructions, cause the apparatus to: determine at least one actuallyavailable random access resource based on time location information fora random access resource and time location information for receiving adownlink signal, wherein a time location for the at least one actuallyavailable random access resource does not overlap with a time locationfor receiving the downlink signal; and send a random access preamble toa network device based on the at least one actually available randomaccess resource.
 25. The apparatus according to claim 24, wherein theone or more processors are further configured to execute the programinstructions, cause the apparatus to: receive a random accessconfiguration index, and obtain the time location information for therandom access resource based on the random access configuration index.26. The apparatus according to claim 24, wherein if it is determinedthat a time location for a random access resource overlaps with the timelocation for receiving the downlink signal, the overlapping resource isprioritized for receiving the downlink signal.
 27. The apparatusaccording to claim 24, wherein the one or more processors are furtherconfigured to execute the program instructions, cause the apparatus to:if it is determined that a time location for a random access resourceoverlaps with the time location for receiving the downlink signal, sendthe random access preamble without using the random access resourcewhose time location overlaps with the time location for the downlinksignal.
 28. The apparatus according to claim 24, wherein the one or moreprocessors are further configured to execute the program instructions,cause the apparatus to: if it is determined that a time location for arandom access resource overlaps with the time location for receiving thedownlink signal, sending the random access preamble without using anyrandom access resource that precedes the overlapping random accessresource in an overlapping slot in which the overlapping random accessresource is located.
 29. The apparatus according to claim 24, whereinthe time location is one or more of the following: an orthogonalfrequency division multiplexing (OFDM) symbol, a mini-slot, a slot, asubframe, or a time segment whose duration is H basic time units,wherein H is greater than
 0. 30. The apparatus according to claim 24,wherein the downlink signal is one or more of the following: asynchronization signal block, a system information block, remainingminimum system information (RMSI), a new radio system information block1 (NR SIB1), a new radio system information block 0 (NR SIB0), areserved downlink signal, a semi-statically configured downlinksubframe, a semi-statically configured slot, or a semi-staticallyconfigured OFDM symbol.